Laos–Myanmar border
Entirely the Mekong, from the Chinese border down to where Thailand begins. Britain and France settled on the river in 1896, keeping Siam between their empires as a buffer.
Written from cited sourcesLast checked 29 September 2026Suggest a correction
See it on the globe:Laos →Myanmar →
A river between empires
For centuries the upper Mekong was a frontier between Tai peoples and the Lao kingdom of the middle Mekong. In the late 19th century, as France took control of Indochina, many in Britain feared French expansion towards India. The two powers agreed to keep Siam independent as a buffer, but not in the far north, where British influence pushed into the Shan states under Burmese rule.[1]
An Anglo-French declaration of 15 January 1896 finally made the Mekong the frontier, down its deepest channel from the Chinese border to the mouth of the Nam Kok.[1]
A remote frontier
The border runs through mountains and plateaus, with the Mekong often in deep, gorge-like valleys and rain forest all around. After the communist takeover of China, Chinese Nationalist irregulars operated from bases in northern Burma and Laos, and some stayed and married into local communities.[1]
In 1964 the US Geographer noted that neither government fully controlled the area: the Pathet Lao held almost all of the Lao side, and Shan insurgents were active in Burma. Chinese engineers were building a road from Yunnan through north-western Laos to Houei Sai on the Thai border, not far from the Burmese tripoint.[1]
Timeline
More borders
Sources
- [1]International Boundary Study No. 33: Burma – Laos Boundary · US Department of State, Office of the Geographer · 18 June 1964
Map geometry from Natural Earth via world-atlas. See credits.