In 330 BC, upon Alexander the Molossian's death, the term "Epirus" appears as a single political unit in the ancient Greek records for the first time, under the leadership of the Molossian dynasty. Subsequently, the coinages of the three major Epirote tribal groups came to an end, and a new coinage was issued with the legend Epirotes. After Alexander's I death, Aeacides of Epirus, who succeeded him, espoused the cause of Olympias against Cassander, but was dethroned in 313 BC.

Pyrrhus of Epirus, a Greek general and statesman.

Aeacides's son Pyrrhus came to the throne in 295 BC. Pyrrhus, being a skillful general, was encouraged to aid the Greeks of Tarentum and decided to initiate a major offensive in the Italian peninsula and Sicily. Due to its superior martial abilities, the Epirote army defeated the Romans in the Battle of Heraclea (280 BC). Subsequently, Pyrrhus's forces nearly reached the outskirts of Rome, but had to retreat to avoid an unequal conflict with a more numerous Roman army. The following year, Pyrrhus invaded Apulia (279 BC) and the two armies met in the Battle of Asculum where the Epirotes won the original Pyrrhic victory, at a high cost.

In 277 BC, Pyrrhus captured the Carthaginian fortress in Eryx, Sicily. This prompted the rest of the Carthaginian-controlled cities to defect to Pyrrhus. Meanwhile, he had begun to display despotic behavior towards the Sicilian Greeks and soon Sicilian opinion became inflamed against him. Though he defeated the Carthaginians in battle, he was forced to abandon Sicily.

Pyrrhus's Italian campaign came to an end following the inconclusive Battle of Beneventum (275 BC). Having lost the vast majority of his army, he decided to return to Epirus, which finally resulted in the loss of all his Italian holdings. Because of his costly victories, the term "Pyrrhic victory" is often used for a victory with devastating cost to the victor.

In 233 BC, the last surviving member of the Aeacid royal house, Deidamia, was murdered. Her death brought the Epirote royal family to an abrupt extinction and a federal republic was set up, though with diminished territory, since western Acarnania had asserted its independence, and the Aetolians seized Ambracia, Amphilochia, and the remaining land north of the Ambracian Gulf. The new Epirote capital was therefore established at Phoenice, the political center of the Chaonians. The reasons for the swift fall of the Aeacid dynasty were probably complex. Aetolian pressure must have played a part, and the alliance with Macedonia may have been unpopular; in addition, there were perhaps social tensions. However, Epirus remained a substantial power, unified under the auspices of the Epirote League as a federal state with its own parliament (or synedrion).

In the following years, Epirus faced the growing threat of the expansionist Roman Republic, which fought a series of wars with Macedonia. The League remained neutral in the first two Macedonian Wars but split in the Third Macedonian War (171–168 BC), with the Molossians siding with the Macedonians and the Chaonians and Thesprotians siding with Rome. The outcome was disastrous for Epirus; Molossia fell to Rome in 167 BC and 150,000 of its inhabitants were enslaved.

Succeeding the Antipatrid dynasty in much of Macedonia, Antigonus ruled mostly over Asia Minor and northern Syria. His attempts to take control of the whole of Alexander's empire led to his defeat and death at the Battle of Ipsus in 301 BC. Antigonus's son Demetrius I Poliorcetes survived the battle, and managed to seize control of Macedon itself a few years later, but eventually lost his throne, dying as a prisoner of Seleucus I Nicator. After a period of confusion, Demetrius's son Antigonus II Gonatas was able to establish the family's control over the old Kingdom of Macedon, as well as over most of the Greek city-states, by 276 BC.

It was one of four dynasties established by Alexander's successors, the others being the Seleucid dynasty, Ptolemaic dynasty and Attalid dynasty. The last scion of the dynasty, Perseus of Macedon, who reigned between 179-168 BC, proved unable to stop the advancing Roman legions and Macedon's defeat at the Battle of Pydna signaled the end of the dynasty.

The ruling members of the Antigonid dynasty were:

Antigonid Rulers

King	Reign (BC)	Consort(s)	Comments
Antigonus I Monophthalmus (Western Asian Antigonid kingdom)	306–301 BC	Stratonice	One of Alexander the Great's top generals; a major participant in the so-called "funeral games" following that king's death.
Demetrius I Poliorcetes (Macedon, Cicilia)	294–287 BC	Phila Ptolemais Deïdameia Lanassa ?Eurydice ?Unnamed Illyrian woman	Son of Antigonus I Monophthalmus. Demetrius' wife Phila was a daughter of Antipater, and ancestor of all subsequent Antigonid kings of Macedon, except Antigonus III Doson, through her son Antigonus II Gonatas. Antigonus III Doson was descended from the marriage of Demetrius and Ptolemais, who was a daughter of Ptolemy I Soter and mother of Doson's father, Demetrius the Fair, the ephemeral King of Cyrene. Deïdameia was a daughter of Aeacides of Epirus and sister of Pyrrhus, she had one son, Alexander, by Demetrius. Demetrius had a further two sons, Demetrius the Thin and Corrhagus, the former by an unnamed Illyrian woman, the latter by a woman named Eurydice. Demetrius I Poliorcetes was the first Antigonid king of Macedon.
Antigonus II Gonatas (Macedon)	276–239 BC	Phila	Son of Demetrius Poliorcetes and Phila, grandson of Antigonus I Monophthalmus. His wife, Phila, was the daughter of his sister, Stratonice. Only one known legitimate child, Demetrius II Aetolicus.
Demetrius the Fair (Cyrene)	c. 250 BC	Olympias of Larissa Berenice II	Son of Demetrius I Poliorcetes and Ptolemaïs. Father of Antigonus III Doson and, apparently, Echecrates by Olympias.
Demetrius II Aetolicus (Macedon)	239–229 BC	Stratonice of Macedon Phthia of Epirus Nicaea of Corinth Chryseis	Son of Antigonus II and Phila. Stratonice of Macedon was a daughter of Antiochus I Soter and Stratonice. Phthia of Epirus was a daughter of Alexander II of Epirus and Olympias II of Epirus. Nicaea of Corinth was the widow of Demetrius' cousin, Alexander of Corinth. Chryseis was a former captive of Demetrius. Only known son, Philip by Chryseis, also had a daughter by Stratonice of Macedon, Apama III.
Antigonus III Doson (Macedon)	229–221 BC	Chryseis	Son of Demetrius the Fair and Olympias of Larissa. Children unknown.
Philip V (Macedon)	221–179 BC	Polycratia of Argos	Son of Demetrius II and Chryseis. At least four children: Perseus of Macedon, Apame, Demetrius and Philippus.
Perseus (Macedon)	179–168 BC (died 166 BC)	Laodice V	The last ruler of Macedon. Laodice V was a daughter of the Seleucid king, Seleucus IV Philopator. At least two sons, Philip and Alexander.

The Greek rebel against Rome and last King of Macedonia, Andriscus, claimed to be the son of Perseus.

In 282 BC, Philetaerus deserted Lysimachus, offering himself and the important fortress of Pergamon, along with its treasury, to Seleucus I Nicator, who defeated and killed Lysimachus at the Battle of Corupedium in 281 BC. Seleucus was killed a few months later. Philetaerus, especially after the death of Seleucus, enjoyed considerable autonomy despite being nominally under the Seleucids. He acquired considerable wealth because Pergamon had been the treasure-hold of Lysimachus and extended his power and influence beyond Pergamon. He contributed troops, money and food to the city of Cyzicus, in Mysia, for its defence against the invading Gauls, thus gaining prestige and goodwill for him and his family. He reigned for forty years and built the temple of Demeter on the acropolis, the temple of Athena (Pergamon's patron deity), and Pergamon's first palace. He added considerably to the city's fortifications.

Philetaerus' nephew and adopted son Eumenes I succeeded him upon his death in 263 BC. He rebelled and defeated the Seleucid king Antiochus I Soter near the Lydian capital of Sardis in 261 BC. He freed Pergamon, and greatly increased its territories. He established garrisons, such as Philetaireia, in the north at the foot of Mount Ida, which was named after his adoptive father, and Attaleia, in the east, to the northeast of Thyatira near the sources of the river Lycus, which was named after his grandfather. He also extended his control to the south of the river Caïcus, reaching the Gulf of Cyme. He minted coins with the portrait of Philetaerus, who during his reign had still been depicting the Seleucid king Seleucus I Nicator on his coins.

Pausanias wrote that the greatest achievement of Attalus I (r. 241–197 BC) was his defeat of the Gauls, by which he meant the Galatians, Celts who had migrated to central Asia Minor and established themselves as a major military power. Several years later the Galatians attacked Pergamon with the help of Antiochus Hierax, who rebelled against his brother Seleucus II Callinicus, the king of the Seleucid Empire and wanted to seize Anatolia and make it his independent kingdom. Attalus defeated the Gauls and Antiochus in the battle of Aphrodisium and in a second battle in the east. He then fought Antiochus alone in a battle near Sardis and in the Battle of the Harpasus in Caria in 229 BC. Attalus won a decisive battle and Antiochus left to start a campaign in Mesopotamia. He gained control over Seleucid territories in Asia Minor north of the Taurus Mountains. He repulsed several attempts by Seleucus III Ceraunus, who had succeeded Seleucus II, to recover the lost territory.

In 223 Seleucus III crossed the Taurus, but was assassinated. Achaeus assumed control of the army. Antiochus III the Great then made him governor of Seleucid territories north of the Taurus. Within two years he recovered the lost territories and forced Attalus within the walls of Pergamon. However, he was accused of intending to revolt and to protect himself he proclaimed himself king.

In 218 BC Achaeus undertook an expedition to Selge, south of the Taurus. Attalus recaptured his former territories with the help of some Thracian Gauls. Achaeus returned from his victorious campaign in 217 BC and hostilities between the two resumed. Attalus made an alliance with Antiochus III, who besieged Achaeus in Sardis in 214 BC. Antiochus captured the city and put Achaeus to death in the next year. Attalus regained control over his territories.

The Attalids became allies of Rome during the First Macedonian War (214–205 BC) and supported Rome in subsequent wars. Attalus I, who had helped the Romans in the first war, also provided them with assistance in the Second Macedonian War (200–197 BC).

Eumenes II (r. 197–159 BC) supported Rome in the Roman–Seleucid War (192–188 BC) and in the Third Macedonian War (171–168 BC) In 188 BC, after the war against the Seleucids, the Romans seized the possessions of the defeated Antiochus III the Great in Asia Minor and gave Mysia, Lydia, Phrygia, and Pamphylia to the kingdom of Pergamon and Caria Lycia and Pisidia, in the southwestern corner of Asia Minor, to Rhodes, another Roman ally. Later the Romans gave these possessions of Rhodes to Pergamon.

Before he became king, Attalus II was a military commander. In 190 BC he took part in the Battle of Magnesia, which was the final victory of the Romans in the war against the Seleucids. In 189 BC he led the Pergamene troops which flanked the Roman Army under Gnaeus Manlius Vulso in the Galatian War. In 182–179 BC, he was at war with Pharnaces I of Pontus. He won victories and gained some territory. He acceded to the throne in 159 BC. In 156–154 BC he made war against Prusias II of Bithynia with the help of the Romans. In 154 BC he was also assisted by Ariarathes V of Cappadocia, who provided troops led by his son Demetrius. Attalus expanded his kingdom and founded the cities of Philadelphia and Attalia. In 152 BC the two kings and Rome helped the pretender Alexander Balas to seize the Seleucid throne from Demetrius I Soter. In 149 BC, Attalus helped Nicomedes II Epiphanes to seize the Bithynian throne from his father Prusias II.

The last Attalid king, Attalus III died without issue and bequeathed the kingdom to the Roman Republic in 133 BC.The Romans were reluctant to take on territory in Asia Minor and did not take charge of the kingdom. Aristonicus, claimed to be the illegitimate son of Eumenes II, assumed the dynastic name of Eumenes III, claimed the throne, instigated a rebellion and in 132 BC "occupied Asia, which had been bequested to the Roman people and was supposed to be free". In 131 BC Rome sent an army against him which was defeated. The Romans defeated Eumemes III in 129 BC. They annexed the former kingdom of Pergamon, which became the Roman province of Asia.

In the interior of the Pergamon Altar there is a frieze depicting the life of Telephus, son of Herakles. The ruling dynasty associated Telephus with its city and used him to claim descent from the Olympians. Pergamon, having entered the Greek world much later than its counterparts to the west, could not boast the same divine heritage as older city-states and so had to cultivate its place in Greek mythology retroactively.

• Philetaerus (282–263 BC)
• Eumenes I (263–241 BC)
• Attalus I Soter (241–197 BC)
• Eumenes II (197–159 BC)
• Attalus II Philadelphus (160–138 BC)
• Attalus III (138–133 BC)
• Eumenes III Aristonicus (pretender, 133–129 BC)

In 332 BC, Alexander the Great, King of Macedon, invaded Egypt, which at the time was a satrapy of the Achaemenid Empire known as the Thirty-first Dynasty under Emperor Artaxerxes III. He visited Memphis, and traveled to the oracle of Amun at the Siwa Oasis. The oracle declared him to be the son of Amun.

Alexander conciliated the Egyptians by the respect he showed for their religion, but he appointed Macedonians to virtually all the senior posts in the country, and founded a new Greek city, Alexandria, to be the new capital. The wealth of Egypt could now be harnessed for Alexander's conquest of the rest of the Achaemenid Empire. Early in 331 BC he was ready to depart, and led his forces away to Phoenicia. He left Cleomenes of Naucratis as the ruling nomarch to control Egypt in his absence. Alexander never returned to Egypt.

Following Alexander's death in Babylon in 323 BC, a succession crisis erupted among his generals. Initially, Perdiccas ruled the empire as regent for Alexander’s half-brother Arrhidaeus, who became Philip III of Macedon, and then as regent for both Philip III and Alexander's infant son Alexander IV of Macedon, who had not been born at the time of his father's death. Perdiccas appointed Ptolemy, one of Alexander’s closest companions, to be satrap of Egypt. Ptolemy ruled Egypt from 323 BC, nominally in the name of the joint kings Philip III and Alexander IV. However, as Alexander the Great's empire disintegrated, Ptolemy soon established himself as ruler in his own right. Ptolemy successfully defended Egypt against an invasion by Perdiccas in 321 BC, and consolidated his position in Egypt and the surrounding areas during the Wars of the Diadochi (322–301 BC). In 305 BC, Ptolemy took the title of King. As Ptolemy I Soter (“Saviour”), he founded the Ptolemaic dynasty that was to rule Egypt for nearly 300 years.

All the male rulers of the dynasty took the name Ptolemy, while princesses and queens preferred the names Cleopatra, Arsinoë and Berenice. Because the Ptolemaic kings adopted the Egyptian custom of marrying their sisters, many of the kings ruled jointly with their spouses, who were also of the royal house. This custom made Ptolemaic politics confusingly incestuous, and the later Ptolemies were increasingly feeble. The only Ptolemaic Queens to officially rule on their own were Berenice III and Berenice IV. Cleopatra V did co-rule, but it was with another female, Berenice IV. Cleopatra VII officially co-ruled with Ptolemy XIII Theos Philopator, Ptolemy XIV, and Ptolemy XV, but effectively, she ruled Egypt alone.

The early Ptolemies did not disturb the religion or the customs of the Egyptians. They built magnificent new temples for the Egyptian gods and soon adopted the outward display of the pharaohs of old. During the reign of Ptolemies II and III, thousands of Macedonian veterans were rewarded with grants of farm lands, and Macedonians were planted in colonies and garrisons or settled themselves in villages throughout the country. Upper Egypt, farthest from the centre of government, was less immediately affected, even though Ptolemy I established the Greek colony of Ptolemais Hermiou to be its capital. But within a century, Greek influence had spread through the country and intermarriage had produced a large Greco-Egyptian educated class. Nevertheless, the Greeks always remained a privileged minority in Ptolemaic Egypt. They lived under Greek law, received a Greek education, were tried in Greek courts, and were citizens of Greek cities.

Ptolemy I

The first part of Ptolemy I's reign was dominated by the Wars of the Diadochi between the various successor states to the empire of Alexander. His first objective was to hold his position in Egypt securely, and secondly to increase his domain. Within a few years he had gained control of Libya, Coele-Syria (including Judea), and Cyprus. When Antigonus, ruler of Syria, tried to reunite Alexander's empire, Ptolemy joined the coalition against him. In 312 BC, allied with Seleucus, the ruler of Babylonia, he defeated Demetrius, the son of Antigonus, in the battle of Gaza.

In 311 BC, a peace was concluded between the combatants, but in 309 BC war broke out again, and Ptolemy occupied Corinth and other parts of Greece, although he lost Cyprus after a sea-battle in 306 BC. Antigonus then tried to invade Egypt but Ptolemy held the frontier against him. When the coalition was renewed against Antigonus in 302 BC, Ptolemy joined it, but neither he nor his army were present when Antigonus was defeated and killed at Ipsus. He had instead taken the opportunity to secure Coele-Syria and Palestine, in breach of the agreement assigning it to Seleucus, thereby setting the scene for the future Syrian Wars. Thereafter Ptolemy tried to stay out of land wars, but he retook Cyprus in 295 BC.

Feeling the kingdom was now secure, Ptolemy shared rule with his son Ptolemy II by Queen Berenice in 285 BC. He then may have devoted his retirement to writing a history of the campaigns of Alexander—which unfortunately was lost but was a principal source for the later work of Arrian. Ptolemy I died in 283 BC at the age of 84. He left a stable and well-governed kingdom to his son.

Ptolemy II

Ptolemy II Philadelphus, who succeeded his father as pharaoh of Egypt in 283 BC, was a peaceful and cultured pharaoh, and no great warrior. He did not need to be, because his father had left Egypt strong and prosperous. Three years of campaigning at the start of his reign (called the First Syrian War) left Ptolemy the master of the eastern Mediterranean, controlling the Aegean islands (the Nesiotic League) and the coastal districts of Cilicia, Pamphylia, Lycia and Caria. However, some of these territories were lost near the end of his reign as a result of the Second Syrian War. In the 270s BC, Ptolemy II defeated the Kingdom of Kush in war, gaining the Ptolemies free access to Kushite territory and control of important gold-mining areas south of Egypt known as Dodekasoinos. As a result, the Ptolemies established hunting stations and ports as far south as Port Sudan, from where raiding parties containing hundreds of men searched for war elephants. Hellenistic culture would acquire an important influence on Kush at this time.

Ptolemy’s first wife, Arsinoe I, daughter of Lysimachus, was the mother of his legitimate children. After her repudiation he followed Egyptian custom and married his sister, Arsinoe II, beginning a practice that, while pleasing to the Egyptian population, had serious consequences in later reigns. The material and literary splendour of the Alexandrian court was at its height under Ptolemy II. Callimachus, keeper of the Library of Alexandria, Theocritus and a host of other poets, glorified the Ptolemaic family. Ptolemy himself was eager to increase the library and to patronise scientific research. He spent lavishly on making Alexandria the economic, artistic and intellectual capital of the Hellenistic world. It is to the academies and libraries of Alexandria that we owe the preservation of so much Greek literary heritage.

Ptolemy III Euergetes

Ptolemy III Euergetes ("the Benefactor") succeeded his father in 246 BC. He abandoned his predecessors' policy of keeping out of the wars of the other Macedonian successor kingdoms, and plunged into the Third Syrian War (246-241 BC) with the Seleucid Empire of Syria, when his sister, Queen Berenice and her son were murdered in a dynastic dispute. Ptolemy marched triumphantly into the heart of the Seleucid realm, as far as Babylonia, while his fleets in the Aegean Sea made fresh conquests as far north as Thrace.

This victory marked the zenith of the Ptolemaic power. Seleucus II Callinicus kept his throne, but Egyptian fleets controlled most of the coasts of Anatolia and Greece. After this triumph Ptolemy no longer engaged actively in war, although he supported the enemies of Macedon in Greek politics. His domestic policy differed from his father's in that he patronised the native Egyptian religion more liberally: he left larger traces among the Egyptian monuments. In this his reign marks the gradual Egyptianisation of the Ptolemies.

Ptolemy IV

In 221 BC, Ptolemy III died and was succeeded by his son Ptolemy IV Philopator, a weak king under whom the decline of the Ptolemaic kingdom began. His reign was inaugurated by the murder of his mother, and he was always under the influence of royal favourites, male and female, who controlled the government. Nevertheless, his ministers were able to make serious preparations to meet the attacks of Antiochus III the Great on Coele-Syria, and the great Egyptian victory of Raphia in 217 BC secured the kingdom. A sign of the domestic weakness of his reign was the rebellions by native Egyptians that took away over half the country for over 20 years. Philopator was devoted to orgiastic religions and to literature. He married his sister Arsinoë, but was ruled by his mistress Agathoclea.

Ptolemy V Epiphanes and Ptolemy VI Philometor

Ptolemy V Epiphanes, son of Philopator and Arsinoë, was a child when he came to the throne, and a series of regents ran the kingdom. Antiochus III the Great of The Seleucid Empire and Philip V of Macedon made a compact to seize the Ptolemaic possessions. Philip seized several islands and places in Caria and Thrace, while the battle of Panium in 200 BC transferred Coele-Syria from Ptolemaic to Seleucid control. After this defeat Egypt formed an alliance with the rising power in the Mediterranean, Rome. Once he reached adulthood Epiphanes became a tyrant, before his early death in 180 BC. He was succeeded by his infant son Ptolemy VI Philometor.

In 170 BC, Antiochus IV Epiphanes invaded Egypt and captured Philometor, installing him at Memphis as a puppet king. Philometor's younger brother (later Ptolemy VIII Physcon) was installed as king by the Ptolemaic court in Alexandria. When Antiochus withdrew, the brothers agreed to reign jointly with their sister Cleopatra II. They soon fell out, however, and quarrels between the two brothers allowed Rome to interfere and to steadily increase its influence in Egypt. Philometor eventually regained the throne. In 145 BC, he was killed in the Battle of Antioch.

Philometor was succeeded by yet another infant, his son Ptolemy VII Neos Philopator. But Physcon soon returned, killed his young nephew, seized the throne and as Ptolemy VIII soon proved himself a cruel tyrant. On his death in 116 BC he left the kingdom to his wife Cleopatra III and her son Ptolemy IX Philometor Soter II. The young king was driven out by his mother in 107 BC, who reigned jointly with Euergetes's youngest son Ptolemy X Alexander I. In 88 BC Ptolemy IX again returned to the throne, and retained it until his death in 80 BC. He was succeeded by Ptolemy XI Alexander II, the son of Ptolemy X. He was lynched by the Alexandrian mob after murdering his stepmother, who was also his cousin, aunt and wife. These sordid dynastic quarrels left Egypt so weakened that the country became a de facto protectorate of Rome, which had by now absorbed most of the Greek world.

Ptolemy XI was succeeded by a son of Ptolemy IX, Ptolemy XII Neos Dionysos, nicknamed Auletes, the flute-player. By now Rome was the arbiter of Egyptian affairs, and annexed both Libya and Cyprus. In 58 BC Auletes was driven out by the Alexandrian mob, but the Romans restored him to power three years later. He died in 51 BC, leaving the kingdom to his ten-year-old son and seventeen-year-old daughter, Ptolemy XIII Theos Philopator and Cleopatra VII, who reigned jointly as husband and wife.

Cleopatra

Cleopatra VII ascended the Egyptian throne at the age of seventeen upon the death of her father, Ptolemy XII Neos Dionysos. She reigned as queen "philopator" and pharaoh with various male co-regents from 51 to 30 BC when she died at the age of 39.

The demise of the Ptolemies' power coincided with the growing dominance of the Roman Republic. With one empire after another falling to Macedon and the Seleucid empire, the Ptolemies had little choice but to ally with the Romans, a pact that lasted over 150 years. By Cleopatra's time, Rome had achieved a massive amount of influence over Egyptian politics and finances to the point that the Roman senate was eventually declared the guardian of the Ptolemaic Dynasty by Cleopatra's father, Ptolemy XII, who had paid vast sums of Egyptian wealth and resources in tribute to the Romans in order to regain and secure his throne following the rebellion and brief coup led by his older daughters, Tryphaena and Berenice IV. Both daughters were killed in Auletes' reclaiming of his throne; Tryphaena by assassination and Berenice by execution, leaving Cleopatra VII as the oldest surviving child of Ptolemy Auletes. Traditionally, Ptolemaic royal siblings were married to one another on ascension to the throne. These marriages sometimes produced children, and other times were only a ceremonial union to consolidate political power. Ptolemy Auletes expressed his wish for Cleopatra and her brother Ptolemy XIII to marry and rule jointly in his will, in which the Roman senate was named as executor, giving Rome further control over the Ptolemies and, thereby, the fate of Egypt as a nation.

After the death of their father, Cleopatra VII and her younger brother Ptolemy XIII inherited the throne and were married. Their marriage was only nominal, however, and their relationship soon degenerated. Cleopatra was finally stripped of authority and title by Ptolemy XIII's advisors, who held considerable influence over the young king. Fleeing into exile, Cleopatra would attempt to raise an army to reclaim the throne.

Julius Caesar left Rome for Alexandria in 48 BC in order to quell the looming civil war, as war in Egypt, which was one of Rome's greatest suppliers of grain and other expensive goods, would have had a detrimental effect on trade with Rome, especially on Rome's working-class citizens. During his stay in the Alexandrian palace, he received 22-year-old Cleopatra, allegedly carried to him in secret wrapped in a carpet. Caesar agreed to support Cleopatra's claim to the throne. Ptolemy XIII and his advisors fled the palace, turning the Egyptian forces loyal to the throne against Caesar and Cleopatra, who barricaded themselves in the palace complex until Roman reinforcements could arrive to combat the rebellion, known afterward as the battles in Alexandria. Ptolemy XIII's forces were ultimately defeated at the Battle of the Nile and the king was killed in the conflict, reportedly drowning in the Nile while attempting to flee with his remaining army.

In the summer of 47 BC, having married her younger brother Ptolemy XIV, Cleopatra embarked with Caesar for a two-month trip along the Nile. Together, they visited Dendara, where Cleopatra was being worshiped as pharaoh, an honor beyond Caesar's reach. They became lovers, and she bore him a son, Caesarion. In 45 BC, Cleopatra and Caesarion left Alexandria for Rome, where they stayed in a palace built by Caesar in their honor.

In 44 BC, Caesar was murdered in Rome by several Senators. With his death, Rome split between supporters of Mark Antony and Octavian. When Mark Antony seemed to prevail, Cleopatra supported him and, shortly after, they too became lovers and eventually married in Egypt (though their marriage was never recognized by Roman law, as Antony was married to a Roman woman). Their union produced three children; the twins Cleopatra Selene and Alexander Helios, and another son, Ptolemy Philadelphos.

Mark Antony's alliance with Cleopatra angered Rome even more. Branded a power-hungry enchantress by the Romans, she was accused of seducing Antony to further her conquest of Rome. Further outrage followed at the donations of Alexandria ceremony in autumn of 34 BC in which Tarsus, Cyrene, Crete, Cyprus, and Judaea were all to be given as client monarchies to Antony's children by Cleopatra. In his will Antony expressed his desire to be buried in Alexandria, rather than taken to Rome in the event of his death, which Octavian used against Antony, sowing further dissent in the Roman populace.

Octavian was quick to declare war on Antony and Cleopatra while public opinion of Antony was low. Their naval forces met at Actium, where the forces of Marcus Vipsanius Agrippa defeated the navy of Cleopatra and Antony. Octavian waited for a year before he claimed Egypt as a Roman province. He arrived in Alexandria and easily defeated Mark Antony's remaining forces outside the city. Facing certain death at the hands of Octavian, Antony attempted suicide by falling on his own sword, but survived briefly. He was taken by his remaining soldiers to Cleopatra, who had barricaded herself in her mausoleum, where he died soon after.

Knowing that she would be taken to Rome to be paraded in Octavian's triumph (and likely executed thereafter), Cleopatra and her handmaidens committed suicide on 12 August 30 BC. Legend and numerous ancient sources claim that she died by way of the venomous bite of an asp, though others state that she used poison, or that Octavian ordered her death himself.

Caesarion, her son by Julius Caesar, nominally succeeded Cleopatra until his capture and supposed execution in the weeks after his mother's death. Cleopatra's children by Antony were spared by Octavian and given to his sister (and Antony's Roman wife) Octavia Minor, to be raised in her household. No further mention is made of Cleopatra and Antony's sons, Alexander Helios and Ptolemy Philadelphus, in the known historical texts of that time, but their daughter Cleopatra Selene was eventually married through arrangement by Octavian into the Mauretanian royal line. Through her offspring, the Ptolemaic line intermarried back into the Roman nobility for centuries.

With the deaths of Cleopatra and Caesarion, the dynasty of Ptolemies and the entirety of pharaonic Egypt came to an end. Alexandria remained the capital of the country, but Egypt itself became a Roman province. Octavian became the sole ruler of Rome and began converting it into a monarchy, the Roman Empire.

Roman rule

Under Roman rule, Egypt was governed by a prefect selected by the emperor from the Equestrian class and not a governor from the Senatorial order, to prevent interference by the Roman Senate. The main Roman interest in Egypt was always the reliable delivery of grain to the city of Rome. To this end the Roman administration made no change to the Ptolemaic system of government, although Romans replaced Greeks in the highest offices. But Greeks continued to staff most of the administrative offices and Greek remained the language of government except at the highest levels. Unlike the Greeks, the Romans did not settle in Egypt in large numbers. Culture, education and civic life largely remained Greek throughout the Roman period. The Romans, like the Ptolemies, respected and protected Egyptian religion and customs, although the cult of the Roman state and of the Emperor was gradually introduced.

The Ancient Library of Alexandria.

Ptolemy I, perhaps with advice from Demetrius of Phalerum, founded the Museum and Library of Alexandria. The Museum was a research centre supported by the king. It was located in the royal sector of the city. The scholars were housed in the same sector and funded by the Ptolemaic rulers. The chief librarian served also as the crown prince’s tutor. For the first hundred and fifty years of its existence this library and research centre drew the top Greek scholars. It was a key academic, literary and scientific centre.

The Ancient Library of Alexandria.

Greek culture

Euclides.

Bone, Robert Trewick: Hypatia Teaching at Alexandria Hypatia Teaching at Alexandria, watercolour and brown ink on paper by Robert Trewick Bone; in the Yale Center for British Art, New Haven, Connecticut.

Terracotta Hadra hydria (water jar), 3rd century BC, Greek, Ptolemaic; On body and neck, laurel sprays between bands. (The Met)

Ptolemaic art was produced during the reign of the Ptolemaic Rulers (304–30 BC), and was concentrated primarily within the bounds of the Ptolemaic Empire. At first, artworks existed separately in either the Egyptian or the Hellenistic style, but over time, these characteristics began to combine. The continuation of the Egyptian art style evidences the Ptolemies' commitment to maintaining Egyptian customs. This strategy not only helped to legitimize their rule, but also placated the general population. Greek-style art was also created during this time and existed in parallel to the more traditional Egyptian art, which could not be altered significantly without changing its intrinsic, primarily-religious function. Art found outside of Egypt itself, though within the Ptolemaic Kingdom, sometimes used Egyptian iconography as it had been used previously, and sometimes adapted it.

Marble head of a Ptolemaic queen, ca. 270–250 BC, Greek. (The Met) Description This monumental head gives an impression of sovereign calm and power, even though the veil that once covered the top and back of the head is now missing. Although the features are cast in a thoroughly classical style typical of the late fourth century B.C., the face is stamped with enough individuality to identify it as a portrait. In all probability, it represents a member of the Ptolemaic dynasty, that succession of Macedonian Greeks who ruled Egypt from the death of Alexander the Great in 323 B.C. until the annexation of Egypt by Rome and the suicide of Cleopatra VII in 30 B.C. Most recently, the head has been identified as Arsinoe II, who ruled together with her brother, Ptolemy II, from 278 B.C. until her death in 270 B.C. Not only was the queen part of a dynastic ruler cult during her life, she was also transformed into an independent deity by her brother after her death. She was worshiped as an Egyptian goddess in association with Isis and also separately as a Greek goddess, with her own sanctuaries and festivals. This strongly idealized head, which resembles classical images of Hera and Demeter, was probably associated with the latter cult.

For example, the faience sistrum inscribed with the name of Ptolemy has some deceptively Greek characteristics, such as the scrolls at the top. However, there are many examples of nearly identical sistrums and columns dating all the way to Dynasty 18 in the New Kingdom. It is, therefore, purely Egyptian in style. Aside from the name of the king, there are other features that specifically date this to the Ptolemaic period. Most distinctively is the color of the faience. Apple green, deep blue, and lavender-blue are the three colors most frequently used during this period, a shift from the characteristic blue of the earlier kingdoms. This sistrum appears to be an intermediate hue, which fits with its date at the beginning of the Ptolemaic empire.

Gold oktadrachm of Ptolemy IV Philopator, 221–204 BC, Greek, Ptolemaic. (The Met)

During the reign of Ptolemy II, Arsinoe II was deified either as stand-alone goddesses or as a personification of another divine figure and given their own sanctuaries and festivals in association to both Egyptian and Hellenistic gods (such as Isis of Egypt and Hera of Greece). For example, Head Attributed to Arsinoe II deified her as an Egyptian goddess. However, the Marble head of a Ptolemaic queen deified Arsinoe II as Hera. Coins from this period also show Arsinoe II with a diadem that is solely worn by goddesses and deified royal women.

The Statuette of Arsinoe II was created c. 150–100 BC, well after her death, as a part of her own specific posthumous cult which was started by her husband Ptolemy II. The figure also exemplifies the fusing of Greek and Egyptian art. Although the backpillar and the goddess's striding pose is distinctively Egyptian, the cornucopia she holds and her hairstyle are both Greek in style. The rounded eyes, prominent lips, and overall youthful features show Greek influence as well.

Limestone block with dedication, late 3rd century BC, Greek, Ptolemaic Egyptian. (The Met) Dedication to Ptolemy IV Philopator (r. 221–204 B.C.) and his sister, Queen Arsinoe, by Teos, son of Horos, who was a guard at the site of Ammonieion, possibly the Temple of Ammon, near Thebes in Upper Egypt.

Despite the unification of Greek and Egyptian elements in the intermediate Ptolemaic period, the Ptolemaic Kingdom also featured prominent temple construction as a continuation of developments based on Egyptian art tradition from the Thirtieth Dynasty. Such behavior expanded the rulers' social and political capital and demonstrated their loyalty toward Egyptian deities, to the satisfaction of the local people. Temples remained very New Kingdom and Late Period Egyptian in style though resources were oftentimes provided by foreign powers. Temples were models of the cosmic world with basic plans retaining the pylon, open court, hypostyle halls, and dark and centrally located sanctuary. However, ways of presenting text on columns and reliefs became formal and rigid during the Ptolemaic Dynasty. Scenes were often framed with textual inscriptions, with a higher text to image ratio than seen previously during the New Kingdom. For example, a relief in the temple of Kom Ombo is separated from other scenes by two vertical columns of texts. The figures in the scenes are smooth, rounded, and high relief, a style continued throughout the 30th Dynasty. The relief represents the interaction between the Ptolemaic kings and the Egyptian deities, which legitimized their rule in Egypt .

Statuette of Isis and Horus, 332–30 BC. (The Met) , For the ancient Egyptians the image of the goddess Isis suckling her son Horus was a powerful symbol of rebirth that was carried into the Ptolemaic period and later transferred to Rome, where the cult of the goddess was established. This piece of faience sculpture joins the tradition of pharaonic Egypt with the artistic style of the Ptolemaic period. On the goddess's head is the throne hieroglyph that represents her name. She also wears a vulture head-covering reserved for queens and goddesses. Following ancient conventions for indicating childhood, Horus is naked and wears a single lock of hair on the right side of his head..

In Ptolemaic art, the idealism seen in the art of previous dynasties continues, with some alterations. Women are portrayed as more youthful, and men begin to be portrayed in a range from idealistic to realistic. An example of realistic portrayal is the Berlin Green Head, which shows the non-idealistic facial features with vertical lines above the bridge of the nose, lines at the corners of the eyes and between the nose and the mouth. The influence of Greek art was shown in an emphasis on the face that was not previously present in Egyptian art and incorporation of Greek elements into an Egyptian setting: individualistic hairstyles, the oval face, “round [and] deeply set” eyes, and the small, tucked mouth closer to the nose. Early portraits of the Ptolemies featured large and radiant eyes in association to the rulers’ divinity as well as general notions of abundance.

When Ptolemy I Soter made himself king of Egypt, he created a new god, Serapis, which was a combination of two Egyptian gods: Apis and Osiris, plus the main Greek gods: Zeus, Hades, Asklepios, Dionysos, and Helios. Serapis had powers over fertility, the sun, funerary rites, and medicine. Many people started to worship this god. In the time of the Ptolemies, the cult of Serapis included the worship of the new Ptolemaic line of pharaohs. Alexandria supplanted Memphis as the preeminent religious city. Ptolemy I also promoted the cult of the deified Alexander, who became the state god of the Ptolemaic kingdom; the Ptolemies eventually associated themselves with the cult as gods.

The wife of Ptolemy II, Arsinoe II, was often depicted in the form of the Greek goddess Aphrodite, but she wore the crown of lower Egypt, with ram's horns, ostrich feathers, and other traditional Egyptian indicators of royalty and/or deification. She wore the vulture headdress only on the religious portion of a relief. Cleopatra VII, the last of the Ptolemaic line, was often depicted with characteristics of the goddess Isis. She often had either a small throne as her headdress or the more traditional sun disk between two horns.

The traditional table for offerings disappeared from reliefs during the Ptolemaic period. Male gods were no longer portrayed with tails in attempt to make them more human-like.

A common stele that appears during the Ptolemaic Dynasty is the cippus, religious objects produced for the purpose of protection of individuals. These magical stelae were made of various materials such as limestone, chlorite schist, and meta-grey-wacke, and were connected with matters of health. Cippi during the Ptolemaic Period featured the child form of the Egyptian god Horus (Horpakhered). This portrayal of Horus refers to the myth wherein Horus triumphs over dangerous animals in the marshes of Khemmis with magic power (also known as Akhmim). Thus, people would keep the Cippus for protection purpose.

The Greeks now formed the new upper classes in Egypt, replacing the old native aristocracy. In general, the Ptolemies undertook changes that went far beyond any other measures that earlier foreign rulers had imposed. They used the religion and traditions to increase their own power and wealth. Although they established a prosperous kingdom, enhanced with fine buildings, the native population enjoyed few benefits, and there were frequent uprisings. These expressions of nationalism reached a peak in the reign of Ptolemy IV Philopator (221–205 BC) when others gained control over one district and ruled as a line of native "pharaohs." This was only curtailed nineteen years later when Ptolemy V Epiphanes (205–181 BC) succeeded in subduing them, but the underlying grievances continued and there were riots again later in the dynasty.

Army

Ptolemaic Egypt, along with the other Hellenistic states outside of the Greek mainland after Alexander the Great, had its armies based on the Macedonian phalanx and featured Macedonian and native troops fighting side by side.

The Ptolemaic military was filled with diverse peoples from across their territories. At first most of the military was made up of a pool of Greek settlers who, in exchange for military service, were given land grants. These made up the majority of the army.

With the many wars the Ptolemies were involved in, their pool of Macedonian troops dwindled and there was little Greek immigration from the mainland so they were kept in the royal bodyguard and as generals and officers. Native troops were looked down upon and distrusted due to their disloyalty and frequent tendency to aid local revolts. However, with the decline of royal power, they gained influence and became common in the military.

The Ptolemies used the great wealth of Egypt to their advantage by hiring vast amounts of mercenaries from across the known world. Black Ethiopians are also known to have served in the military along with the Galatians, Mysians and others.

With their vast amount of territory spread along the Eastern Mediterranean such as Cyprus, Crete, the islands of the Aegean and even Thrace, the Ptolemies required a large navy to defend these far-flung strongholds from enemies like the Seleucids and Macedonians.

Navy

The Ptolemaic Navy was the naval force of the Ptolemaic Kingdom and later empire from 305 to 30 BC. It was founded by King Ptolemy I. Its main naval bases were at Alexandria, Egypt and Nea Paphos or (New Paphos) in Cyprus. It operated in the East Mediterranean in the Aegean Sea, the Levantine Sea, but also on the river Nile and in the Red Sea towards the Indian Ocean. The navy operated four naval forces including the Alexandrian Fleet, the Aegean Fleet, the Red Sea Fleet and a Nile River Fleet.

While ruling Egypt, the Ptolemaic Dynasty built many Greek settlements throughout their Empire, to either Hellenize new conquered peoples or reinforce the area. Egypt had only three main Greek cities—Alexandria, Naucratis, and Ptolemais.

Naucratis

Of the three Greek cities, Naucratis, although its commercial importance was reduced with the founding of Alexandria, continued in a quiet way its life as a Greek city-state. During the interval between the death of Alexander and Ptolemy's assumption of the style of king, it even issued an autonomous coinage. And the number of Greek men of letters during the Ptolemaic and Roman period, who were citizens of Naucratis, proves that in the sphere of Hellenic culture Naucratis held to its traditions. Ptolemy II bestowed his care upon Naucratis. He built a large structure of limestone, about 100 metres (330 ft) long and 18 metres (59 ft) wide, to fill up the broken entrance to the great Temenos; he strengthened the great block of chambers in the Temenos, and re-established them. At the time when Sir Flinders Petrie wrote the words just quoted the great Temenos was identified with the Hellenion. But Mr. Edgar has recently pointed out that the building connected with it was an Egyptian temple, not a Greek building. Naucratis, therefore, in spite of its general Hellenic character, had an Egyptian element. That the city flourished in Ptolemaic times "we may see by the quantity of imported amphorae, of which the handles stamped at Rhodes and elsewhere are found so abundantly." The Zeno papyri show that it was the chief port of call on the inland voyage from Memphis to Alexandria, as well as a stopping-place on the land-route from Pelusium to the capital. It was attached, in the administrative system, to the Saïte nome.

Alexandria

A major Mediterranean port of Egypt, in ancient times and still today, Alexandria was founded in 331 BC by Alexander the Great. According to Plutarch, the Alexandrians believed that Alexander the Great's motivation to build the city was his wish to "found a large and populous Greek city that should bear his name." Located 30 kilometres (19 mi) west of the Nile's westernmost mouth, the city was immune to the silt deposits that persistently choked harbors along the river. Alexandria became the capital of the Hellenized Egypt of King Ptolemy I (reigned 323–283 BC). Under the wealthy Ptolemaic Dynasty, the city soon surpassed Athens as the cultural center of the Hellenic world.

Laid out on a grid pattern, Alexandria occupied a stretch of land between the sea to the north and Lake Mareotis to the south; a man-made causeway, over three-quarters of a mile long, extended north to the sheltering island of Pharos, thus forming a double harbor, east and west. On the east was the main harbor, called the Great Harbor; it faced the city's chief buildings, including the royal palace and the famous Library and Museum. At the Great Harbor's mouth, on an outcropping of Pharos, stood the lighthouse, built c. 280 BC. Now vanished, the lighthouse was reckoned as one of the Seven Wonders of the World for its unsurpassed height (perhaps 140 metres or 460 ft); it was a square, fenestrated tower, topped with a metal fire basket and a statue of Zeus the Savior.

The Library, at that time the largest in the world, contained several hundred thousand volumes and housed and employed scholars and poets. A similar scholarly complex was the Museum (Mouseion, "hall of the Muses"). During Alexandria's brief literary golden period, c. 280–240 BC, the Library subsidized three poets—Callimachus, Apollonius of Rhodes, and Theocritus—whose work now represents the best of Hellenistic literature. Among other thinkers associated with the Library or other Alexandrian patronage were the mathematician Euclid (c. 300 BC), the inventor Archimedes (287 BC – c. 212 BC), and the polymath Eratosthenes (c. 225 BC).

Cosmopolitan and flourishing, Alexandria possessed a varied population of Greeks, Egyptians and other Oriental peoples, including a sizable minority of Jews, who had their own city quarter. Periodic conflicts occurred between Jews and ethnic Greeks. According to Strabo, Alexandria had been inhabited during Polybius' lifetime by local Egyptians, foreign mercenaries and the tribe of the Alexandrians, whose origin and customs Polybius identified as Greek.

The city enjoyed a calm political history under the Ptolemies. It passed, with the rest of Egypt, into Roman hands in 30 BC, and became the second city of the Roman Empire.

Ptolemais

The second Greek city founded after the conquest of Egypt was Ptolemais, 400 miles (640 km) up the Nile, where there was a native village called Psoï, in the nome called after the ancient Egyptian city of Thinis. If Alexandria perpetuated the name and cult of the great Alexander, Ptolemais was to perpetuate the name and cult of the founder of the Ptolemaic time. Framed in by the barren hills of the Nile Valley and the Egyptian sky, here a Greek city arose, with its public buildings and temples and theatre, no doubt exhibiting the regular architectural forms associated with Greek culture, with a citizen-body Greek in blood, and the institutions of a Greek city. If there is some doubt whether Alexandria possessed a council and assembly, there is none in regard to Ptolemais. It was more possible for the kings to allow a measure of self-government to a people removed at that distance from the ordinary residence of the court. We have still, inscribed on stone, decrees passed in the assembly of the people of Ptolemais, couched in the regular forms of Greek political tradition: It seemed good to the boule and to the demos: Hermas son of Doreon, of the deme Megisteus, was the proposer: Whereas the prytaneis who were colleagues with Dionysius the son of Musaeus in the 8th year, etc.

The Ptolemaic kingdom was diverse in the people who settled and made Egypt their home at this time. During this period, Macedonian troops under Ptolemy I Soter were given land grants and brought their families encouraging tens of thousands of Greeks to settle the country making themselves the new ruling class. Native Egyptians continued having a role, albeit a small one, in the Ptolemaic government, mostly in lower posts, and outnumbered the foreigners. During the reign of the Ptolemaic Pharaohs, many Jews were imported from neighboring Judea by the thousands for being renowned fighters and established an important presence there. Other foreign groups settled, and even Galatian mercenaries were invited. Of the aliens who had come to settle in Egypt, the ruling group, the Greeks, were the most important element. They were partly spread as allotment-holders over the country, forming social groups, in the country towns and villages, side by side with the native population, partly gathered in the three Greek cities, the old Naucratis, founded before 600 BC (in the interval of Egyptian independence after the expulsion of the Assyrians and before the coming of the Persians), and the two new cities, Alexandria by the sea, and Ptolemais in Upper Egypt. Alexander and his Seleucid successors founded many Greek cities all over their dominions.

Greek culture was so much bound up with the life of the city-state that any king who wanted to present himself to the world as a genuine champion of Hellenism had to do something in this direction, but the king of Egypt, ambitious to shine as a Hellene, would find Greek cities, with their republican tradition and aspirations to independence, inconvenient elements in a country that lent itself, as no other did, to bureaucratic centralization. The Ptolemies therefore limited the number of Greek city-states in Egypt to Alexandria, Ptolemais, and Naucratis.

Outside of Egypt, they had Greek cities under their dominion, including the old Greek cities in the Cyrenaica, in Cyprus, on the coasts and islands of the Aegean, but they were smaller than the three big ones in Egypt. There were indeed country towns with names such as Ptolemais, Arsinoe, and Berenice, in which Greek communities existed with a certain social life and there were similar groups of Greeks in many of the old Egyptian towns, but they were not communities with the political forms of a city-state. Yet if they had no place of political assembly, they would have their gymnasium, the essential sign of Hellenism, serving something of the purpose of a university for the young men. Far up the Nile at Ombi a gymnasium of the local Greeks was found in 136–135 BC, which passed resolutions and corresponded with the king. Also, in 123 BC, when there was trouble in Upper Egypt between the towns of Crocodilopolis and Hermonthis, the negotiators sent from Crocodilopolis were the young men attached to the gymnasium, who, according to the Greek tradition, ate bread and salt with the negotiators from the other town. All the Greek dialects of the Greek world gradually became assimilated in the Koine Greek dialect that was the common language of the Hellenistic world. Generally, the Greeks of Ptolemaic Egypt felt like representatives of a higher civilization but were curious about the native culture of Egypt.

Jews

The Jews who lived in Egypt had originally immigrated from the Southern Levant. The Jews absorbed Greek, the dominant language of Egypt at the time, and heavily mixed it with Hebrew. The Septuagint, the Greek translation of the Jewish scriptures, appeared and was written by seventy Jewish Translators under royal compulsion during Ptolemy II's reign. That is confirmed by historian Flavius Josephus, who writes that Ptolemy, desirous to collect every book in the habitable earth, applied Demetrius Phalereus to the task of organizing an effort with the Jewish high priests to translate the Jewish books of the Law for his library. Josephus thus places the origins of the Septuagint in the 3rd century BC, when Demetrius and Ptolemy II lived. According to Jewish legend, the seventy wrote their translations independently from memory, and the resultant works were identical at every letter.

Arabs

In 1990, more than 2,000 papyri written by Zeno of Caunus from the time of Ptolemy II Philadelphus were discovered, which contained at least 19 references to Arabs in the area between the Nile and the Red Sea, and mentioned their jobs as police officers in charge of "ten person units", and some others were mentioned as shepherds. Arabs in the Ptolemaic kingdom had provided camel convoys to the armies of some Ptolemaic leaders during their invasions, but they had allegiance to none of the kingdoms of Egypt or Syria, and they managed to raid and attack both sides of the conflict between the Ptolemaic Kingdom and its enemies.

Contemporary sources, such as a loyalist decree honoring Antiochus I from Ilium, in Greek language define the Seleucid state both as an empire (arche) and as a kingdom (basileia). Similarly, Seleucid rulers were described as kings in Babylonia.

Starting from the 2nd century BC, ancient writers referred to the Seleucid ruler as the King of Syria, Lord of Asia, and other designations; the evidence for the Seleucid rulers representing themselves as kings of Syria is provided by the inscription of Antigonus son of Menophilus, who described himself as the "admiral of Alexander, king of Syria". He refers to either Alexander Balas or Alexander II Zabinas as a ruler.

Alexander, who quickly conquered the Persian Empire under its last Achaemenid dynast, Darius III, died young in 323 BC, leaving an expansive empire of partly Hellenised culture without an adult heir. The empire was put under the authority of a regent in the person of Perdiccas, and the territories were divided among Alexander's generals, who thereby became satraps, at the Partition of Babylon, all in that same year.

Alexander's generals (the Diadochi) jostled for supremacy over parts of his empire. Ptolemy, a former general and the satrap of Egypt, was the first to challenge the new system; this led to the demise of Perdiccas. Ptolemy's revolt led to a new subdivision of the empire with the Partition of Triparadisus in 320 BC. Seleucus, who had been "Commander-in-Chief of the Companion cavalry" (hetairoi) and appointed first or court chiliarch (which made him the senior officer in the Royal Army after the regent and commander-in-chief Perdiccas since 323 BC, though he helped to assassinate him later) received Babylonia and, from that point, continued to expand his dominions ruthlessly. Seleucus established himself in Babylon in 312 BC, the year used as the foundation date of the Seleucid Empire.

The rise of Seleucus in Babylon threatened the eastern extent of Antigonus I territory in Asia. Antigonus, along with his son Demetrius I of Macedon, unsuccessfully led a campaign to annex Babylon. The victory of Seleucus ensured his claim of Babylon and legitimacy. He ruled not only Babylonia, but the entire enormous eastern part of Alexander's empire, as described by Appian:

“Always lying in wait for the neighboring nations, strong in arms and persuasive in council, he [Seleucus] acquired Mesopotamia, Armenia, 'Seleucid' Cappadocia, Persis, Parthia, Bactria, Arabia, Tapouria, Sogdia, Arachosia, Hyrcania, and other adjacent peoples that had been subdued by Alexander, as far as the river Indus, so that the boundaries of his empire were the most extensive in Asia after that of Alexander. The whole region from Phrygia to the Indus was subject to Seleucus.” (Appian, History of Rome, The Syrian Wars 55)

Following his and Lysimachus' victory over Antigonus Monophthalmus at the decisive Battle of Ipsus in 301 BC, Seleucus took control over eastern Anatolia and northern Syria.

In the latter area, he founded a new capital at Antioch on the Orontes, a city he named after his father. An alternative capital was established at Seleucia on the Tigris, north of Babylon. Seleucus's empire reached its greatest extent following his defeat of his erstwhile ally, Lysimachus, at Corupedion in 281 BC, after which Seleucus expanded his control to encompass western Anatolia. He hoped further to take control of Lysimachus's lands in Europe – primarily Thrace and even Macedonia itself, but was assassinated by Ptolemy Ceraunus on landing in Europe.

His son and successor, Antiochus I Soter, was left with an enormous realm consisting of nearly all of the Asian portions of the Empire, but faced with Antigonus II Gonatas in Macedonia and Ptolemy II Philadelphus in Egypt, he proved unable to pick up where his father had left off in conquering the European portions of Alexander's empire.

Antiochus I (reigned 281–261 BC) and his son and successor Antiochus II Theos (reigned 261-246 BC) were faced with challenges in the west, including repeated wars with Ptolemy II and a Celtic invasion of Asia Minor — distracting attention from holding the eastern portions of the Empire together. Towards the end of Antiochus II's reign, various provinces simultaneously asserted their independence, such as Bactria and Sogdiana under Diodotus, Cappadocia under Ariarathes III, and Parthia under Andragoras. A few years later, the latter was defeated and killed by the invading Parni of Arsaces – the region would then become the core of the Parthian Empire.

Diodotus, governor for the Bactrian territory, asserted independence in around 245 BC, although the exact date is far from certain, to form the Greco-Bactrian Kingdom. This kingdom was characterized by a rich Hellenistic culture and was to continue its domination of Bactria until around 125 BC when it was overrun by the invasion of northern nomads. One of the Greco-Bactrian kings, Demetrius I of Bactria, invaded India around 180 BC to form the Indo-Greek Kingdoms.

The rulers of Persis, called Fratarakas, also seem to have established some level of independence from the Seleucids during the 3rd century BC, especially from the time of Vahbarz. They would later overtly take the title of Kings of Persis, before becoming vassals to the newly formed Parthian Empire.

The Seleucid satrap of Parthia, named Andragoras, first claimed independence, in a parallel to the secession of his Bactrian neighbour. Soon after, however, a Parthian tribal chief called Arsaces invaded the Parthian territory around 238 BC to form the Arsacid dynasty, from which the Parthian Empire originated.

Antiochus II's son Seleucus II Callinicus came to the throne around 246 BC. Seleucus II was soon dramatically defeated in the Third Syrian War against Ptolemy III of Egypt and then had to fight a civil war against his own brother Antiochus Hierax. Taking advantage of this distraction, Bactria and Parthia seceded from the empire. In Asia Minor too, the Seleucid dynasty seemed to be losing control: the Gauls had fully established themselves in Galatia, semi-independent semi-Hellenized kingdoms had sprung up in Bithynia, Pontus, and Cappadocia, and the city of Pergamum in the west was asserting its independence under the Attalid Dynasty. The Seleucid economy started to show the first signs of weakness, as Galatians gained independence and Pergamum took control of coastal cities in Anatolia. Consequently, they managed to partially block contact with the West.

A revival would begin when Seleucus II's younger son, Antiochus III the Great, took the throne in 223 BC. Although initially unsuccessful in the Fourth Syrian War against Egypt, which led to a defeat at the Battle of Raphia (217 BC), Antiochus would prove himself to be the greatest of the Seleucid rulers after Seleucus I himself. He spent the next ten years on his anabasis (journey) through the eastern parts of his domain and restoring rebellious vassals like Parthia and Greco-Bactria to at least nominal obedience. He won the Battle of the Arius and besieged the Bactrian capital, and even emulated Alexander with an expedition into India where he met with king Sophagasenus (Sanskrit: Subhagasena) receiving war elephants.

Actual translation of Polybius 11.34 (No other source except Polybius makes any reference to Sophagasenus):

"He (Antiochus) crossed the Caucasus Indicus (Paropamisus) (Hindu Kush) and descended into India; renewed his friendship with Sophagasenus the king of the Indians; received more elephants, until he had a hundred and fifty altogether; and having once more provisioned his troops, set out again personally with his army: leaving Androsthenes of Cyzicus the duty of taking home the treasure which this king had agreed to hand over to him. Having traversed Arachosia and crossed the river Enymanthus, he came through Drangene to Carmania; and as it was now winter, he put his men into winter quarters there."

When he returned to the west in 205 BC, Antiochus found that with the death of Ptolemy IV, the situation now looked propitious for another western campaign. Antiochus and Philip V of Macedon then made a pact to divide the Ptolemaic possessions outside of Egypt, and in the Fifth Syrian War, the Seleucids ousted Ptolemy V from control of Coele-Syria. The Battle of Panium (198 BC) definitively transferred these holdings from the Ptolemies to the Seleucids. Antiochus appeared, at the least, to have restored the Seleucid Kingdom to glory.

Expansion into Greece and war with Rome

Following the defeat of his erstwhile ally Philip by Rome in 197 BC, Antiochus saw the opportunity for expansion into Greece itself. Encouraged by the exiled Carthaginian general Hannibal, and making an alliance with the disgruntled Aetolian League, Antiochus launched an invasion across the Hellespont. With his huge army he aimed to establish the Seleucid empire as the foremost power in the Hellenic world, but these plans put the empire on a collision course with the new rising power of the Mediterranean, the Roman Republic. At the battles of Thermopylae (191 BC) and Magnesia (190 BC), Antiochus's forces suffered resounding defeats, and he was compelled to make peace and sign the Treaty of Apamea (188 BC), the main clause of which saw the Seleucids agree to pay a large indemnity, to retreat from Anatolia and to never again attempt to expand Seleucid territory west of the Taurus Mountains. The Kingdom of Pergamum and the Republic of Rhodes, Rome's allies in the war, gained the former Seleucid lands in Anatolia. Antiochus died in 187 BC on another expedition to the east, where he sought to extract money to pay the indemnity.

The reign of his son and successor Seleucus IV Philopator (187-175 BC) was largely spent in attempts to pay the large indemnity, and Seleucus was ultimately assassinated by his minister Heliodorus.

Seleucus' younger brother, Antiochus IV Epiphanes, now seized the throne. He attempted to restore Seleucid power and prestige with a successful war against the old enemy, Ptolemaic Egypt, which met with initial success as the Seleucids defeated and drove the Egyptian army back to Alexandria itself. As the king planned on how to conclude the war, he was informed that Roman commissioners, led by the Proconsul Gaius Popillius Laenas, were near and requesting a meeting with the Seleucid king. Antiochus agreed, but when they met and Antiochus held out his hand in friendship, Popilius placed in his hand the tablets on which was written the decree of the senate and told him to read it. When the king said that he would call his friends into council and consider what he ought to do, Popilius drew a circle in the sand around the king's feet with the stick he was carrying and said, "Before you step out of that circle give me a reply to lay before the senate." For a few moments he hesitated, astounded at such a peremptory order, and at last replied, "I will do what the senate thinks right." He then chose to withdraw rather than set the empire to war with Rome again.

The latter part of his reign saw a further disintegration of the Empire despite his best efforts. Weakened economically, militarily and by loss of prestige, the Empire became vulnerable to rebels in the eastern areas of the empire, who began to further undermine the empire while the Parthians moved into the power vacuum to take over the old Persian lands. Antiochus' aggressive Hellenizing (or de-Judaizing) activities provoked a full scale armed rebellion in Judea — the Maccabean Revolt. Efforts to deal with both the Parthians and the Jews as well as retain control of the provinces at the same time proved beyond the weakened empire's power. Antiochus died during a military expedition against the Parthians in 164 BC.

After the death of Antiochus IV Epiphanes, the Seleucid Empire became increasingly unstable. Frequent civil wars made central authority tenuous at best. Epiphanes' young son, Antiochus V Eupator, was first overthrown by Seleucus IV's son, Demetrius I Soter in 161 BC. Demetrius I attempted to restore Seleucid power in Judea particularly, but was overthrown in 150 BC by Alexander Balas – an impostor who (with Egyptian backing) claimed to be the son of Epiphanes. Alexander Balas reigned until 145 BC when he was overthrown by Demetrius I's son, Demetrius II Nicator. Demetrius II proved unable to control the whole of the kingdom, however. While he ruled Babylonia and eastern Syria from Damascus, the remnants of Balas' supporters – first supporting Balas' son Antiochus VI, then the usurping general Diodotus Tryphon – held out in Antioch.

Meanwhile, the decay of the Empire's territorial possessions continued apace. By 143 BC, the Jews in the form of the Maccabees had fully established their independence. Parthian expansion continued as well. In 139 BC, Demetrius II was defeated in battle by the Parthians and was captured. By this time, the entire Iranian Plateau had been lost to Parthian control.

Demetrius Nicator's brother, Antiochus VII Sidetes, took the throne after his brother's capture. He faced the enormous task of restoring a rapidly crumbling empire, one facing threats on multiple fronts. Hard-won control of Coele-Syria was threatened by the Jewish Maccabee rebels. Once-vassal dynasties in Armenia, Cappadocia, and Pontus were threatening Syria and northern Mesopotamia; the nomadic Parthians, brilliantly led by Mithridates I of Parthia, had overrun upland Media (home of the famed Nisean horse herd); and Roman intervention was an ever-present threat. Sidetes managed to bring the Maccabees to heel and frighten the Anatolian dynasts into a temporary submission; then, in 133, he turned east with the full might of the Royal Army (supported by a body of Jews under the Hasmonean prince, John Hyrcanus) to drive back the Parthians.

Sidetes' campaign initially met with spectacular success, recapturing Mesopotamia, Babylonia, and Media. In the winter of 130/129 BC, his army was scattered in winter quarters throughout Media and Persis when the Parthian king, Phraates II, counter-attacked. Moving to intercept the Parthians with only the troops at his immediate disposal, he was ambushed and killed. Antiochus Sidetes is sometimes called the last great Seleucid king.

After the death of Antiochus VII Sidetes, all of the recovered eastern territories were recaptured by the Parthians. The Maccabees again rebelled, civil war soon tore the empire to pieces, and the Armenians began to encroach on Syria from the north.

By 100 BC, the once formidable Seleucid Empire encompassed little more than Antioch and some Syrian cities. Despite the clear collapse of their power, and the decline of their kingdom around them, nobles continued to play kingmakers on a regular basis, with occasional intervention from Ptolemaic Egypt and other outside powers. The Seleucids existed solely because no other nation wished to absorb them – seeing as they constituted a useful buffer between their other neighbours. In the wars in Anatolia between Mithridates VI of Pontus and Sulla of Rome, the Seleucids were largely left alone by both major combatants.

Mithridates' ambitious son-in-law, Tigranes the Great, king of Armenia, however, saw opportunity for expansion in the constant civil strife to the south. In 83 BC, at the invitation of one of the factions in the interminable civil wars, he invaded Syria and soon established himself as ruler of Syria, putting the Seleucid Empire virtually at an end.

Seleucid rule was not entirely over, however. Following the Roman general Lucullus' defeat of both Mithridates and Tigranes in 69 BC, a rump Seleucid kingdom was restored under Antiochus XIII. Even so, civil wars could not be prevented, as another Seleucid, Philip II, contested rule with Antiochus. After the Roman conquest of Pontus, the Romans became increasingly alarmed at the constant source of instability in Syria under the Seleucids. Once Mithridates was defeated by Pompey in 63 BC, Pompey set about the task of remaking the Hellenistic East, by creating new client kingdoms and establishing provinces. While client nations like Armenia and Judea were allowed to continue with some degree of autonomy under local kings, Pompey saw the Seleucids as too troublesome to continue; doing away with both rival Seleucid princes, he made Syria into a Roman province.

The Seleucid empire's geographical span, from the Aegean Sea to what is now Afghanistan and Pakistan, created a melting pot of various peoples, such as Greeks, Armenians, Georgians, Persians, Medes, Assyrians and Jews. The immense size of the empire, followed by its encompassing nature, encouraged the Seleucid rulers to implement a policy of ethnic unity—a policy initiated by Alexander.

The Hellenization of the Seleucid empire was achieved by the establishment of Greek cities throughout the empire. Historically significant towns and cities, such as Antioch, were created or renamed with more appropriate Greek names. The creation of new Greek cities and towns was aided by the fact that the Greek mainland was overpopulated and therefore made the vast Seleucid empire ripe for colonization. Colonization was used to further Greek interest while facilitating the assimilation of many native groups. Socially, this led to the adoption of Greek practices and customs by the educated native classes in order to further themselves in public life, and at the same time the ruling Macedonian class gradually adopted some of the local traditions. By 313 BC, Hellenic ideas had begun their almost 250-year expansion into the Near East, Middle East, and Central Asian cultures. It was the empire's governmental framework to rule by establishing hundreds of cities for trade and occupational purposes. Many of the existing cities began—or were compelled by force—to adopt Hellenized philosophic thought, religious sentiments, and politics although the Seleucid rulers did incorporate Babylonian religious tenets to gain support.

Synthesizing Hellenic and indigenous cultural, religious, and philosophical ideas met with varying degrees of success—resulting in times of simultaneous peace and rebellion in various parts of the empire. Such was the case with the Jewish population of the Seleucid empire; the Jews' refusal to willingly Hellenize their religious beliefs or customs posed a significant problem which eventually led to war. Contrary to the accepting nature of the Ptolemaic empire towards native religions and customs, the Seleucids gradually tried to force Hellenization upon the Jewish people in their territory by outlawing Judaism. This eventually led to the revolt of the Jews under Seleucid control, which would later lead to the Jews achieving independence from the Seleucid empire.