In the mid-19th century the Tibetans repeatedly rebuffed overtures from the British, who at first saw Tibet as a trade route to China and later as countenancing Russian advances that might endanger India. Eventually, in 1903, after failure to get China to control its unruly vassal, a political mission was dispatched from India to secure understandings on frontier and trade relations. Tibetan resistance was overcome by force, the Dalai Lama fled to China, and the rough wooing ended in a treaty at Lhasa in 1904 between Britain and Tibet without Chinese adherence. In 1906, however, the Chinese achieved a treaty with Britain, without Tibetan participation, that recognized their suzerainty over Tibet. Success emboldened the Chinese to seek direct control of Tibet by using force against the Tibetans for the first time in 10 centuries. In 1910 the Dalai Lama again was forced to flee, this time to India.

That dying burst by the Manchu dynasty converted Tibetan indifference into enmity, and, after the Chinese Revolution in 1911-12, the Tibetans expelled all the Chinese and declared their independence of the new republic. Tibet functioned as an independent government until 1951 and defended its frontier against China in occasional fighting as late as 1931. In 1949, however, the "liberation" of Tibet was heralded, and in October 1950 the Chinese invaded eastern Tibet, overwhelming the poorly equipped Tibetan troops. An appeal by the Dalai Lama to the United Nations was denied, and support from India and Britain was not forthcoming. A Tibetan delegation summoned to China in 1951 had to sign a treaty dictated by the conquerors. It professed to guarantee Tibetan autonomy and religion but also allowed the establishment at Lhasa of Chinese civil and military headquarters.

Smoldering resentment at the strain on the country's resources from the influx of Chinese soldiery and civilians was inflamed in 1956 by reports of savage fighting and oppression in districts east of the upper Yangtze, outside the administration of Lhasa but bound to it by race, language, and religion. Refugees from the fighting in the east carried guerrilla warfare against the Chinese into central Tibet, creating tensions that exploded in a popular rising at Lhasa in March 1959. The Dalai Lama, most of his ministers, and many followers escaped across the Himalayas, and the rising was suppressed.

The events of 1959 intensified China's disagreements with India, which had given asylum to the Dalai Lama, and in 1962 Chinese forces proved the efficiency of the new communications by invading northeast Assam.

In 1966 and 1967 the Chinese position was shaken by Red Guard excesses and internecine fighting when the Cultural Revolution reached Lhasa. Military control was restored by 1969; and in 1971 a new local government committee was announced. Between 1963 and 1971 no foreign visitor was allowed to enter Tibet. Persecution of Tibetans abated in the late 1970s with the end of the Cultural Revolution, but Chinese repression was resumed when the Tibetans renewed their claims for autonomy and even independence. However, China has invested in the economic development of Tibet and in the early 1980s took initiatives to repair diplomatic ties with the Dalai Lama. Despite China's efforts to restore some freedoms and ease its repressive posture, riots broke out in the late 1980s, and China imposed martial law in Tibet in 1988. Tibet continues to suffer from periodic unrest, and China's suppression of political and religious freedoms has led to Western criticism and protests by human rights organizations. The Dalai Lama, still unrecognized by the Chinese government, won the Nobel Peace Price in 1989.