Xinjiang is the Chinese name for the Tarim and Dzungaria regions of what is now northwest China. At the beginning of the Han Dynasty (206 BC-220 AD), the entire region was ruled by the Xiongnu, a powerful nomadic people based in modern Mongolia.

In the 2nd century BC, Han China sent Zhang Qian, a Chinese explorer and imperial envoy, to the states in the region. Zhang Qian's visit began several decades of conflict between the Xiongnu and Han China over the dominance of the region, which eventually commenced in Chinese success.

In 60 BC, Han China established the Protectorate of the Western Regions at Wulei to oversee the entire region.

 

Zhang Qian leaving emperor Han Wudi around 130 BCE, for his expedition to Central Asia. Mogao Caves, high Tang Dynasty, circa 8th century CE. Photo courtesy of Wikipedia.

 

The dependent states of the protectorate later rebelled during the usurpation of Wang Mang, a Han Dynasty official who seized the throne from the Liu family and founded the Xin Dynasty, and the region fell under Xiongnu rule again.

Over the next century, Han China sent several expeditions into the region and re-established the protectorate. After the fall of the Han Dynasty in 220 AD, the protectorate was maintained by the Wei Dynasty until 265 AD, and by the Western Jin Dynasty from 265 AD onward.