On 3 July 1914, in Simla, the Simla Convention is signed — the agreement among Britain, China and Tibet on Tibet’s status and the border with British India, including the McMahon Line.

Talks led by Henry McMahon produced a map of the north-eastern frontier; the Chinese representative initialled it, but Beijing refused ratification, leaving a long-running dispute.

Tibet and the British proceeded on a bilateral understanding; China permanently contested the McMahon Line’s validity.

The Convention remains a key — and contested — document of the Sino-Indian border dispute in Arunachal Pradesh / South Tibet.

For imperial diplomacy, 3 July 1914 marks the attempt to fix Tibet’s status and the north-eastern frontier.

Text and maps are documented in British archives and treaty collections.

The Simla Convention of 3 July 1914 remains the disputed milestone of the McMahon Line.

Image: Shimla / Himalaya; Wikimedia Commons. Cropped to 16:9.

Source consulted: Simla Convention. Treaty text: Convention Between Great Britain, China, and Tibet, Simla (1914).