The Inner Mongolia Autonomous Region was established in 1947, Xinjiang was made autonomous in 1955, and Guangxi and Ningxia were made autonomous in 1958. Tibet was placed under PRC control in 1951, with some Western observers calling this an annexation, and was named a Chinese Autonomous Zone in 1965. The designation of Guangxi and Ningxia as Zhuang and Hui autonomous areas, respectively, was bitterly protested by the local Han Chinese, who made up two-thirds of the population of each region. Although Mongols made up an even smaller percentage of Inner Mongolia than either of these, the ensuing Chinese Civil War gave little opportunity for protest.