It has been described on at least one occasion as sharing similarities with the "U.S. federal government's recognition of some Native American tribes as in some ways sovereign entities." "Tusi" were located primarily in the province of Yunnan and in the regions of Guizhou, Tibet, Sichuan and Chongqing, Xiangxi Prefecture of Hunan, and Enshi Prefecture of Hubei. "Tusi" also existed in the historic dependencies of China in what is today northern Myanmar, Laos, and northern Thailand. Vietnam also implemented a "tusi" system under the Nguyễn dynasty (1802–1945).