The Yuan emperor established the Xuanzheng Yuan or Ministry for the Spread of Governance to directly handle important military and political affairs of the Tibet region. Choice of its members lay with the emperor and its reports were submitted directly to the monarch.
The central government of the Yuan Dynasty sent officials into Tibet to set up post stations, whose size varied according to the local population, topography and resources. These post stations were linked up in a communication line extending from Tibet up to Dadu (present-day Beijing).
The central government of the Yuan Dynasty also dispatched officials into Tibet to conduct censuses, establish the number of corvee laborers in areas under various wanhu offices and decide the number of corvee laborers, provisions and animal transport the areas along the post route had to supply. Such censuses were conducted three times in Tibet, in 1268, 1287 and 1334..”