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.
Xiongnu
Harold Walter Bailey proposed an Iranian origin of the Xiongnu, recognizing all the earliest Xiongnu names of the 2nd century BC as being of the Iranian type. This theory is supported by turkologist . Central Asian scholar Christopher I. Beckwith notes that the Xiongnu name could be a cognate of Scythian, Saka and Sogdia, corresponding to a name for Northern Iranians. According to Beckwith the Xiongnu could have contained a leading Iranian component when they started out, but more likely they had earlier been subjects of an Iranian people and learned from them the Iranian nomadic model.