Simla Convention

The Simla Accord, or the Convention Between Great Britain, China, and Tibet, [in] Simla, was a treaty concerning the status of Tibet negotiated by representatives of the Republic of China, Tibet and the United Kingdom in Simla in 1913 and 1914.

The Accord provided that Tibet would be divided into "Outer Tibet" and "Inner Tibet". Outer Tibet, which roughly corresponded to Ü-Tsang and western Kham, would "remain in the hands of the Tibetan Government at Lhasa under Chinese suzerainty, but China would not interfere in its administration. "Inner Tibet", roughly, equivalent to Amdo and eastern Kham, would be under the jurisdiction of the Chinese government. The Accord with its annexes also defines the boundary between Tibet and China proper and between Tibet and British India (the latter became known as the McMahon Line).

China rejected the Accord and their plenipotentiary, Ivan Chen, withdrew on 3 July 1914. The British and Tibetan plenipotentiaries then attached a note denying China any privileges under the Accord and sealed it as a bilateral agreement the same day. The British records show that there are conditions for the Tibetan government to accept the new border in 1914, the condition was that China must accept the Simla Convention, since the British was not able to get an aceptance form China, Tibetans considered the MacMahon line invalid.

McMahon's work was initially rejected by the British government as incompatible with the 1907 Anglo-Russian Convention. This convention was renounced in 1921. The British began using the McMahon Line on Survey of India maps in 1937, and the Simla Accord was published officially in 1938.

Early British efforts to create a boundary for north-east India were triggered by their discovery in the mid-19th century that Tawang, an important trading town, was Tibetan territory. Britain had concluded treaties with Qing China concerning Tibet's boundaries with Burma and Sikkim. However, Tibet refused to recognise the boundaries drawn by these treaties. British forces led by Sir Francis Younghusband entered Tibet in 1904 and made a treaty with the Tibetans. In 1907, Britain and Russia acknowledged Chinese "suzerainty" over Tibet.

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