Arunachal Pradesh

The McMahon Line

In October 1913 British, Chinese and Tibetan representatives met at Shimla, in the Himalayan foothills, to settle Tibet’s borders. The conference drew a line between India and Tibet named after the chief British negotiator, Sir Henry McMahon. It runs about 890 km along the crest of the Himalayas, from Bhutan to the great bend of the Brahmaputra and on to the tip of Myanmar.^[2]

Britain and Tibet accepted the terms. China refused to sign, because it held that Tibet was part of China and had no power to make treaties.^[2] The People’s Republic, founded in 1949, did not recognise the convention either. In 1959 Premier Zhou Enlai wrote to Jawaharlal Nehru that the line “has never been recognised by any Chinese Central Government and is therefore decidedly illegal.”^[2]

War and statehood

In the 1962 war Chinese troops crossed the McMahon Line into what was then the North East Frontier Agency. After a unilateral ceasefire they withdrew behind the line again.^[2] The agency had been part of Assam; it became the union territory of Arunachal Pradesh in 1972 and a state in 1987.^[1]

In October 1975 four Indian soldiers were killed at Tulung La. India said Chinese troops ambushed its patrol; China said it acted in self-defence. In 1987 the two armies faced each other in the Sumdorong Chu valley, and India’s decision to make Arunachal Pradesh a state angered China, which calls the region South Tibet. The standoff ended without bloodshed.^[4] Scuffles broke out again at Yangtse, in the Tawang sector, in December 2022.^[5][6]

China’s claim has grown. In the mid-1980s Beijing claimed only the Tawang area; in the 2000s it began to claim all of Arunachal Pradesh.^[4] China says the boundary has never been delimited and claims the land south of the McMahon Line as southern Tibet. India treats the McMahon Line as the international border.^[3]

Names on the map

Since 2017 China’s Ministry of Civil Affairs has issued lists of “standardised” Chinese names for places in the state: 6 in 2017, 15 in 2021, 11 in 2023, 30 in 2024 and 27 in May 2025.^[3] A sixth list, of 23 passes, peaks, rivers and settlements, followed on 10 April 2026.^[7] China says the naming “is fully within China’s sovereignty.”^[3]

India rejects each list. In 2023 its foreign ministry said Arunachal Pradesh “is, has been and will always be an integral and inalienable part of India”.^[5] In 2025 it called the renaming “vain and preposterous”, and said “creative naming will not alter the undeniable reality”.^[3]