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.
Huns
In the 18th century, the French scholar Joseph de Guignes became the first to propose a link between the Huns and the Xiongnu people, who were northern neighbours of China in the 3rd century BC. Since Guignes' time, considerable scholarly effort has been devoted to investigating such a connection. However, there is no scholarly consensus on a direct connection between the dominant element of the Xiongnu and that of the Huns.