Why did the Qing Dynasty set up a minister stationed in Tibet?

He was the minister stationed in Tibet established in the Qing Dynasty.

China, the chief executive of the central government of the Qing Dynasty in Tibet. The full name is "imperial envoy to Tibet", also known as "imperial envoy to Tibet". There is one deputy director and one deputy director with the title of "Deputy Minister". Founded in the fifth year of Yongzheng (1727), Xuantong for three years (19 1 1) and 184, there were 83 ministers in Tibet, including 57 (including re-election and re-election).