Xiongnu, or Hsiung-nu, Nomadic pastoral people of Central Asia. The Xiongnu at the end of the 3rd century bc formed a great tribal league that dominated much of Central Asia for more than 500 years. Their threat to the northern Chinese frontier throughout this period led to China’s eventual conquest of northern Korea and southern Manchuria during the Han dynasty. Excavation of Xiongnu graves has revealed remains of Chinese, Iranian, and Greek textiles, indicating a wide trade with distant peoples.