The great Han general Ban Chao had written a request to the Emperor in 100 CE, saying, among other things: "I have taken care to send my son (Ban) Yong to enter the frontier following porters with presents, and thus, I will arrange things so that (Ban) Yong sees the Middle Territories [usually referred to as the 'Western Regions'—mainly the kingdoms in and around the Tarim Basin] with his own eyes while I am still alive." (From the Hou Hanshu (Book of the Later Han), Chapter 77 [sometimes given as Chapter 47], translated and adapted by E. Chavannes.).

The Western Regions in modern Xinjiang province in 107 CE had rebelled against Chinese rule.

Ban Yong had been appointed as a major and, with his elder brother, Ban Xiong, had gone via Dunhuang to meet up with the Protector General of the Western Regions, Ren Shang (?-119 CE), who had replaced Ban Chao as Protector General in 102 CE.

The Chinese had been forced to retreat and, following this, there have been no Chinese functionaries in the Western Regions for more than ten years.

Emperor An in 123 CE gives Ban Yong the title of 'Senior Clerk of the Western Regions' so that he can lead five hundred freed convicts west to garrison Liuzhong (Lukchun, in the southern Turpan Basin).

Ban Yong afterward conquers and pacifies Turpan and …