Tibet (; Böd; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa, Tamang, Qiang, Sherpa and Lhoba peoples and now also considerable numbers of Han Chinese and Hui settlers. Since 1951, the entire plateau has been under the administration of the People's Republic of China, a major portion in the Tibet Autonomous Region, and other portions in the Qinghai and Sichuan provinces. Tibet is the highest region on Earth, with an average elevation of . Located in the Himalayas, the highest elevation in Tibet is Mount Everest, Earth's highest mountain, rising 8,848.86 m (29,032 ft) above sea level. The Tibetan Empire emerged in the 7th century. At its height in the 9th century, the Tibetan Empire extended far beyond the Tibetan Plateau, from Central Asian's Tarim Basin and the Pamirs in the west to Yunnan and Bengal in the southeast. But once the process of fragmentation began, the empire divided into a variety of territories. The bulk of western and central Tibet (Ü-Tsang) was often at least nominally unified under a series of Tibetan governments in Lhasa, Shigatse, or nearby locations. The eastern regions of Kham and Amdo often maintained a more decentralized indigenous political structure, being divided among a number of small principalities and tribal groups, while also often falling more directly under Chinese rule; most of this area was eventually annexed into the Chinese provinces of Sichuan and Qinghai. The current borders of Tibet were generally established in the 18th century. Following the Xinhai Revolution against the Qing dynasty in 1912, Qing soldiers were disarmed and escorted out of Tibet Area (Ü-Tsang). The region subsequently declared its independence in 1913 without recognition and permission by the subsequent Chinese Republican government. Later, Lhasa took control of the western part of Xikang. The region maintained its autonomy until 1951 when, following the Battle of Chamdo, Tibet was occupied and annexed into the People's Republic of China, and the previous Tibetan government was abolished in 1959 after a failed uprising. Today, China governs western and central Tibet as the Tibet Autonomous Region while the eastern areas are now mostly ethnic autonomous prefectures within Sichuan, Qinghai and other neighbouring provinces. There are tensions regarding Tibet's political status and dissident groups that are