What is "yuezhi"

The Yuèzhī or Rouzhi (; Old Chinese 月支) were an ancient Indo-European people who were first reported living in an arid grassland area spanning the modern Chinese provinces of Xinjiang and Gansu, before the 2nd century BCE.

After a major defeat by the Xiongnu, the Yuezhi fragmented, during the 2nd Century BCE, into groups that emigrated in different directions. The Greater Yuezhi or Great Yuezhi (Da Yuezhi 大月氏) migrated west through the Tarim Basin into the Ili Valley (on the modern borders of China and Kazakhstan), where they reportedly displaced elements of the Sakas ( Scythians). Most members of another group, the Lesser Yuezhi or Little Yuezhi (Xiao Yuezhi 小月氏) reportedly moved south, towards the Tibetan Plateau. The Greater Yuezhi were driven from the Ili Valley by the Wusun and migrated southward to Sogdia and, later, Bactria, where they displaced the Greco-Bactrian Kingdom. The Greater Yuezhi were consequently often identified with the Tókharioi (Greek Τοχάριοι; Sanskrit Tukhāra) and Asii or Asioi mentioned in classical European sources.

During the 1st Century BCE, one of the five major Yuezhi tribes in Bactria, the Kushanas , began to subsume the other tribes and neighbouring peoples. The subsequent Kushan Empire, at its peak in the 3rd Century CE, stretched from Turfan in the Tarim Basin, in the north to Pataliputra on the Gangetic plain of India in the south. The Kushanas played an important role in the development of trade on the Silk Road and the introduction of Buddhism to China.