History generally considers the Xianbei to have Mongolic origins. Their first leader, Tanshihuai, unified scattered clans and invaded both the Xiongnu and the Chinese. He rose to power at a young age and achieved numerous political objectives for the Xianbei nation. He eliminated the Xiongnu threat and in 158 secured the southern borders by attacking the Chinese. The latter retaliated with an army of 30,000 soldiers, which proved victorious. Tanshihuai became a recognized leader of Central Asia, though he died young. The Xianbei state subsequently experienced internal conflicts and never achieved unity again.

The period from 250 to 550 was turbulent for Central Asia and China. The Xianbei and Xiongnu attacked China and established several short-lived governments. Each faction warred against the other. The Hun state of Jiao and the Xianbei states of Muyun and Toba dominated this chaotic period of warfare and revolt. Xianbei leaders called themselves "khans"—a term later applied to all nomadic governments.

Some Xianbei declared the Mongolian steppes the Rouran khaganate. It was a vast domain encompassing the entire territory of present-day Mongolia, with power balanced between the Toba empire and the Tibetan realm. Through a sophisticated governmental system, the Rouran effectively controlled the Tele peoples to the west. The Rouran introduced military obedience as an organizing principle. Like the Xiongnu, the Rouran people believed in nature spirits and practiced divination and shamanism. Nevertheless, historical records suggest that Buddhist missionaries were present in the Rouran khaganate and carried out numerous conversions. The monk Dharmapriya in particular converted more than 300 Rouran families.

In the sixth century, the bitter war between the Rouran and the Toba empire came to an end. Toba, a Xianbei province in China, fell into the hands of people who reclaimed control of their lands. The Rouran suffered from mutinies among their subject peoples, particularly the Turks. In 545, the Turkic leader Bumin rebelled against Rouran domination and led his people toward China, where they either perished or were assimilated.