In the 2nd and 1st millennia BC, a series of large and powerful states developed on the southern periphery of Central Asia (the Ancient Near East). These empires launched several attempts to conquer the steppe people but met with only mixed success. The Median Empire and Achaemenid Empire both ruled parts of Central Asia. The Xiongnu Empire (209 BC-93 (156) AD) may be seen as the first central Asian empire which set an example for later Göktürk and Mongol empires. Xiongnu's ancestor Xianyu tribe founded Zhongshan state (c. 6th century BC – c. 296 BC) in Hebei province, China. The title chanyu was used by the Xiongnu rulers before Modun Chanyu so it is possible that statehood history of the Xiongnu began long before Modun's rule.

Following the success of the Han–Xiongnu War, Chinese states would also regularly strive to extend their power westwards. Despite their military might, these states found it difficult to conquer the whole region.

When faced by a stronger force, the nomads could simply retreat deep into the steppe and wait for the invaders to leave. With no cities and little wealth other than the herds they took with them, the nomads had nothing they could be forced to defend. An example of this is given by Herodotus’s detailed account of the futile Persian campaigns against the Scythians. The Scythians, like most nomad empires, {!} had permanent settlements of various sizes, representing various degrees of civilisation. The vast fortified settlement of Kamenka on the Dnieper River, settled since the end of the 5th century BC, became the centre of the Scythian kingdom ruled by Ateas, who lost his life in a battle against Philip II of Macedon in 339 BC.

Some empires, such as the Persian and Macedonian empires, did make deep inroads into Central Asia by founding cities and gaining control of the trading centres. Alexander the Great's conquests spread Hellenistic civilisation all the way to Alexandria Eschate (Lit. “Alexandria the Furthest”), established in 329 BC in modern Tajikistan. After Alexander's death in 323 BC, his Central Asian territory fell to the Seleucid Empire during the Wars of the Diadochi.

In 250 BC, the Central Asian portion of the empire (Bactria) seceded as the Greco-Bactrian Kingdom, which had extensive contacts with India and China until its end in 125 BC. The Indo-Greek Kingdom, mostly based in the Punjab region but controlling a fair part of Afghanistan, pioneered the development of Greco-Buddhism. The Kushan Kingdom thrived across a wide swath of the region from the 2nd century BC to the 4th century AD, and continued Hellenistic and Buddhist traditions. These states prospered from their position on the Silk Road linking China and Europe.

Likewise, in eastern Central Asia, the Chinese Han Dynasty expanded into the region at the height of its imperial power. From roughly 115 to 60 BC, Han forces fought the Xiongnu over control of the oasis city-states in the Tarim Basin. The Han was eventually victorious and established the Protectorate of the Western Regions in 60 BC, which dealt with the region's defence and foreign affairs. Chinese rule in Tarim Basin was replaced successively with Kushans and Hephthalites.

Later, external powers such as the Sassanid Empire would come to dominate this trade. One of those powers, the Parthian Empire, was of Central Asian origin, but adopted Persian-Greek cultural traditions. This is an early example of a recurring theme of Central Asian history: occasionally nomads of Central Asian origin would conquer the kingdoms and empires surrounding the region, but quickly merge into the culture of the conquered peoples.

At this time Central Asia was a heterogeneous region with a mixture of cultures and religions. Buddhism remained the largest religion, but was concentrated in the east. Around Persia, Zoroastrianism became important. Nestorian Christianity entered the area, but was never more than a minority faith. More successful was Manichaeism, which became the third largest faith.

Turkic expansion began in the 6th century; the Turkic speaking Uyghurs were one of many distinct cultural groups brought together by the trade of the Silk Route at Turfan, which was then ruled by China's Tang Dynasty. The Uyghurs, primarily pastoral nomads, observed a number of religions including Manichaeism, Buddhism, and Nestorian Christianity. Many of the artefacts from this period were found in the 19th century in this remote desert region.

Sui and early Tang Dynasty

It was during the Sui and Tang dynasties that China expanded into eastern Central Asia. Chinese foreign policy to the north and west now had to deal with Turkic nomads, who were becoming the most dominant ethnic group in Central Asia. To handle and avoid any threats posed by the Turks, the Sui government repaired fortifications and received their trade and tribute missions. They sent royal princesses off to marry Turkic clan leaders, a total of four of them in 597, 599, 614, and 617. The Sui stirred trouble and conflict amongst ethnic groups against the Turks.

As early as the Sui Dynasty, the Turks had become a major militarised force employed by the Chinese. When the Khitans began raiding north-east China in 605, a Chinese general led 20,000 Turks against them, distributing Khitan livestock and women to the Turks as a reward. On two occasions between 635 and 636, Tang royal princesses were married to Turk mercenaries or generals in Chinese service.

Throughout the Tang Dynasty until the end of 755, there were approximately ten Turkic generals serving under the Tang. While most of the Tang army was made of fubing (府兵) Chinese conscripts, the majority of the troops led by Turkic generals were of non-Chinese origin, campaigning largely in the western frontier where the presence of fubing (府兵) troops was low. Some "Turkic" troops were nomadisized Han Chinese, a desinicized people.

Civil war in China was almost totally diminished by 626, along with the defeat in 628 of the Ordos Chinese warlord Liang Shidu; after these internal conflicts, the Tang began an offensive against the Turks. In the year 630, Tang armies captured areas of the Ordos Desert, modern-day Inner Mongolia province, and southern Mongolia from the Turks.

After this military victory, Emperor Taizong won the title of Great Khan amongst the various Turks in the region who pledged their allegiance to him and the Chinese empire (with several thousand Turks traveling into China to live at Chang'an). On June 11, 631, Emperor Taizong also sent envoys to the Xueyantuo bearing gold and silk in order to persuade the release of enslaved Chinese prisoners who were captured during the transition from Sui to Tang from the northern frontier; this embassy succeeded in freeing 80,000 Chinese men and women who were then returned to China.

While the Turks were settled in the Ordos region (former territory of the Xiongnu), the Tang government took on the military policy of dominating the central steppe. Like the earlier Han Dynasty, the Tang Dynasty, along with Turkic allies like the Uyghurs, conquered and subdued Central Asia during the 640s and 650s. During Emperor Taizong's reign alone, large campaigns were launched against not only the Göktürks, but also separate campaigns against the Tuyuhun, and the Xueyantuo. Taizong also launched campaigns against the oasis states of the Tarim Basin, beginning with the annexation of Gaochang in 640. The nearby kingdom of Karasahr was captured by the Tang in 644 and the kingdom of Kucha was conquered in 649.

The expansion into Central Asia continued under Taizong's successor, Emperor Gaozong, who invaded the Western Turks ruled by the qaghan Ashina Helu in 657 with an army led by Su Dingfang. Ashina was defeated and the khaganate was absorbed into the Tang empire. The territory was administered through the Anxi Protectorate and the Four Garrisons of Anxi. Tang hegemony beyond the Pamir Mountains in modern Tajikistan and Afghanistan ended with revolts by the Turks, but the Tang retained a military presence in Xinjiang. These holdings were later invaded by the Tibetan Empire to the south in 670. For the remainder of the Tang Dynasty, the Tarim Basin alternated between Tang and Tibetan rule as they competed for control of Central Asia.

Tang rivalry with the Tibetan Empire

The Tang Empire competed with the Tibetan Empire for control of areas in Inner and Central Asia, which was at times settled with marriage alliances such as the marrying of Princess Wencheng (d. 680) to Songtsän Gampo (d. 649). A Tibetan tradition mentions that after Songtsän Gampo's death in 649 AD, Chinese troops captured Lhasa. The Tibetan scholar Tsepon W. D. Shakabpa believes that the tradition is in error and that "those histories reporting the arrival of Chinese troops are not correct" and claims that the event is mentioned neither in the Chinese annals nor in the manuscripts of Dunhuang.

There was a long string of conflicts with Tibet over territories in the Tarim Basin between 670–692 and in 763 the Tibetans even captured the capital of China, Chang'an, for fifteen days during the An Shi Rebellion. In fact, it was during this rebellion that the Tang withdrew its western garrisons stationed in what is now Gansu and Qinghai, which the Tibetans then occupied along with the territory of what is now Xinjiang. Hostilities between the Tang and Tibet continued until they signed a formal peace treaty in 821. The terms of this treaty, including the fixed borders between the two countries, are recorded in a bilingual inscription on a stone pillar outside the Jokhang temple in Lhasa.

Islamic empires

In the 8th century, Islam began to penetrate the region, the desert nomads of Arabia could militarily match the nomads of the steppe, and the early Arab Empire gained control over parts of Central Asia. The early conquests under Qutayba ibn Muslim (705-715) were soon reversed by a combination of native uprisings and invasion by the Turgesh, but the collapse of the Turgesh khaganate after 738 opened the way for the re-imposition of Muslim authority under Nasr ibn Sayyar.

The Arab invasion also saw Chinese influence expelled from western Central Asia. At the Battle of Talas in 751 an Arab army decisively defeated a Tang Dynasty force, and for the next several centuries Middle Eastern influences would dominate the region. Large-scale Islamization however did not begin until the 9th century, running parallel with the fragmentation of Abbasid political authority and the emergence of local Iranian and Turkic dynasties like the Samanids.

Over time, as new technologies were introduced, the nomadic horsemen grew in power. The Scythians developed the saddle, and by the time of the Alans the use of the stirrup had begun. Horses continued to grow larger and sturdier so that chariots were no longer needed as the horses could carry men with ease. This greatly increased the mobility of the nomads; it also freed their hands, allowing them to use the bow from horseback.

Using small but powerful composite bows, the steppe people gradually became the most powerful military force in the world. From a young age, almost the entire male population was trained in riding and archery, both of which were necessary skills for survival on the steppe. By adulthood, these activities were second nature. These mounted archers were more mobile than any other force at the time, being able to travel forty miles per day with ease.

The steppe peoples quickly came to dominate Central Asia, forcing the scattered city states and kingdoms to pay them tribute or face annihilation. The martial ability of the steppe peoples was limited, however, by the lack of political structure within the tribes. Confederations of various groups would sometimes form under a ruler known as a khan. When large numbers of nomads acted in unison they could be devastating, as when the Huns arrived in Western Europe. However, tradition dictated that any dominion conquered in such wars should be divided among all of the khan's sons, so these empires often declined as quickly as they formed.

Once the foreign powers were expelled, several indigenous empires formed in Central Asia. The Hephthalites were the most powerful of these nomad groups in the 6th and 7th century and controlled much of the region. In the 10th and 11th centuries the region was divided between several powerful states including the Samanid dynasty, that of the Seljuk Turks, and the Khwarezmid Empire.

The most spectacular power to rise out of Central Asia developed when Genghis Khan united the tribes of Mongolia. Using superior military techniques, the Mongol Empire spread to comprise all of Central Asia and China as well as large parts of Russia, and the Middle East. After Genghis Khan died in 1227, most of Central Asia continued to be dominated by the successor Chagatai Khanate. This state proved to be short lived, as in 1369 Timur, a Turkic leader in the Mongol military tradition, conquered most of the region.

Even harder than keeping a steppe empire together was governing conquered lands outside the region. While the steppe peoples of Central Asia found conquest of these areas easy, they found governing almost impossible. The diffuse political structure of the steppe confederacies was maladapted to the complex states of the settled peoples. Moreover, the armies of the nomads were based upon large numbers of horses, generally three or four for each warrior. Maintaining these forces required large stretches of grazing land, not present outside the steppe. Any extended time away from the homeland would thus cause the steppe armies to gradually disintegrate. To govern settled peoples the steppe peoples were forced to rely on the local bureaucracy, a factor that would lead to the rapid assimilation of the nomads into the culture of those they had conquered. Another important limit was that the armies, for the most part, were unable to penetrate the forested regions to the north; thus, such states as Novgorod and Muscovy began to grow in power.

In the 14th century much of Central Asia, and many areas beyond it, were conquered by Timur (1336-1405) who is known in the west as Tamerlane. It was during Timur’s reign that the nomadic steppe culture of Central Asia fused with the settled culture of Iran. One of its consequences was an entirely new visual language that glorified Timur and subsequent Timurid rulers. This visual language was also used to articulate their commitment to Islam. Timur's large empire collapsed soon after his death, however. The region then became divided among a series of smaller Khanates, including the Khanate of Khiva, the Khanate of Bukhara, the Khanate of Kokand, and the Khanate of Kashgar.

The lifestyle that had existed largely unchanged since 500 BCE began to disappear after 1500. Important changes to the world economy in the 14th and 15th century reflected the impact of the development of nautical technology. Ocean trade routes were pioneered by the Europeans, who had been cut off from the Silk Road by the Muslim states that controlled its western termini. The long-distance trade linking East Asia and India to Western Europe increasingly began to move over the seas and not through Central Asia. However, the emergence of Russia as a world power enabled Central Asia to continue its role as a conduit for overland trade of other sorts, now linking India with Russia on a north-south axis.

An even more important development was the introduction of gunpowder-based weapons. The gunpowder revolution allowed settled peoples to defeat the steppe horsemen in open battle for the first time. Construction of these weapons required the infrastructure and economies of large societies and were thus impractical for nomadic peoples to produce. The domain of the nomads began to shrink as, beginning in the 15th century, the settled powers gradually began to conquer Central Asia.

The last steppe empire to emerge was that of the Dzungars who conquered much of East Turkestan and Mongolia. However, in a sign of the changed times they proved unable to match the Chinese and were decisively defeated by the forces of the Qing Dynasty. In the 18th century the Qing emperors, themselves originally from the far eastern edge of the steppe, campaigned in the west and in Mongolia, with the Qianlong Emperor taking control of Xinjiang in 1758. The Mongol threat was overcome and much of Inner Mongolia was annexed to China.

The Chinese dominions stretched into the heart of Central Asia and included the Khanate of Kokand, which paid tribute to Beijing. Outer Mongolia and Xinjiang did not become provinces of the Chinese empire, but rather were directly administered by the Qing dynasty. The fact that there was no provincial governor meant that the local rulers retained most of their powers and this special status also prevented emigration from the rest of China into the region. Persia also began to expand north, especially under the rule of Nadir Shah, who extended Persian dominion well past the Oxus. After his death, however, the Persian empire rapidly crumbled.

The Russians also expanded south, first with the transformation of the Ukrainian steppe into an agricultural heartland, and subsequently onto the fringe of the Kazakh steppes, beginning with the foundation of the fortress of Orenburg. The slow Russian conquest of the heart of Central Asia began in the early 19th century, although Peter the Great had sent a failed expedition under Prince Bekovitch-Cherkassky against Khiva as early as the 1720s.

By the 1800s, the locals could do little to resist the Russian advance, although the Kazakhs of the Great Horde under Kenesary Kasimov rose in rebellion from 1837–46. Until the 1870s, for the most part, Russian interference was minimal, leaving native ways of life intact and local government structures in place. With the conquest of Turkestan after 1865 and the consequent securing of the frontier, the Russians gradually expropriated large parts of the steppe and gave these lands to Russian farmers, who began to arrive in large numbers. This process was initially limited to the northern fringes of the steppe and it was only in the 1890s that significant numbers of Russians began to settle farther south, especially in Zhetysu (Semirechye).