FACTBOX: Historical ties between China and Tibet

(Reuters) - At the heart of the conflict over Tibet's status within China is their historical relationship.

The Chinese government and Tibet's government-in-exile offer competing versions of whether the remote, mountainous territory was historically ruled as part of China, or whether it has legitimate claims to independence or autonomy.

Following are some details about the history of relations.

THE IMPERIAL ERA

- Most historians agree Tibet's assimilation into China was established during the Yuan dynasty (1271-1368). In China's view, the relationship continued throughout the next two dynasties, the Ming and the Qing.

But the nature of relations is complicated by several factors:

- During the Yuan dynasty, China and Tibet were ruled by the Mongols under Kublai Khan. The Qing dynasty (1644-1911) was similarly a period of foreign rule by the Manchus.

- The relationship between China and Tibet varied over the centuries depending on the relative strength or weakness of the imperial government. The Qing emperors were especially weak towards the end of their reign, when British and other foreign forces began making inroads.

- Some say that over these centuries the relationship of Tibet to China is best described as that of a vassal state, but there are disputes over the nature of the priest-patron ties and whether Tibet was viewed as subordinate.

THE REPUBLICAN ERA

- The 13th Dalai Lama Tibet expelled Chinese troops stationed in Lhasa in the chaos following the 1911 revolution. He declared independence in 1912, and Tibet largely ruled itself until 1950, when China struggled with foreign invasion and civil wars. But China's Republican government maintained its claim to Tibet.

- In support of Tibet's claim to independence during this period, scholars note it had its own foreign affairs bureau, remained neutral during World War Two and issued passports.

- But neither China nor any major Western power recognized it as independent and China's government refused to accept the border between British India and Tibet drawn up at the 1913-14 Simla Conference. Britain agreed in the convention to recognize China's suzerainty over Tibet but also autonomy for the area roughly conforming to the present-day Tibet Autonomous Region.

THE COMMUNIST ERA

- China says it had no choice but to dispatch People's Liberation Army troops to Tibet in 1950 after local leaders there refused to negotiate its "peaceful liberation".

- Under the 17-point Agreement of 1951, China pledged to keep Tibet's traditional government and religion in place. But Communist land reform and collectivization left the region in turmoil, and in 1959 the Dalai Lama led an uprising against Chinese rule, despite his initial support of the 1951 accord.