Nomadic empire
The Xiongnu were a confederation of nomadic tribes from Central Asia with a ruling class of unknown origin and other subjugated tribes. They lived on the Mongolian Plateau between the 3rd century BC and the 460s AD, their territories including modern day Mongolia, southern Siberia, western Manchuria, and the modern Chinese provinces of Inner Mongolia, Gansu, and Xinjiang. The Xiongnu was the first unified empire of nomadic peoples. Relations between early Chinese dynasties and the Xiongnu were complicated and included military conflict, exchanges of tribute and trade, and marriage treaties. When Emperor Qin Shihuang drove them away from the south of the Yellow River, he built the famous Great Wall to prevent the Xiongnu from coming back.
Five Barbarians
In the 190s CE the Southern Xiongnu revolted against attempts of the Chinese Court to appoint a puppet Southern Shanyu against their will:
The Southern Xiongnu then elected a Shanyu from the Xubu in 188 CE and Chizhishizhuhou Chanyu (188–195 CE) fled back to the Chinese court. After the death of the new Shanyu in 196 CE, most of the Southern Xiongnu left to join the Northern Xiongnu and only five tribes remained in China.