Thailand's War With Vichy France
The story of an almost unknown war and its international repercussions on the eve of Pearl Harbor.
In late 1940 and early 1941 the Vichy French in Indochina and Thailand fought a short, bitter and now forgotten war. The conflict, over Thai claims to territories annexed by France, has been noteworthy to military historians solely because of a surprising French naval victory. French firmness against Thailand had also been stiffened by a tragi-comic misunderstanding with the Japanese over their agreed takeover of northern Indochina in September 1940.
Vichy success against Thailand was a severe embarrassment to the Japanese, who swiftly nullified the effect of the French triumph at the conference table, forcing France to cede substantial portions of Indochina to the aggrieved Thais. Although the war itself was a small sideshow which had no decisive bearing on the course of the wider Pacific struggle to come, the conflict and Japan's manipulation of both players was intended to improve Japan's strategic position. This it certainly did, reinforcing the ambitions of the 'Strike South' faction in the Japanese military.
Before 1941 was out, Japanese troops in Indochina and Thailand were striking further afield, to Malaya and Singapore to the south and Burma to the west, in their doomed quest for a 'Greater East Asia Co-Prosperity Sphere' under their imperial control.
The conflict between Thailand and Vichy France cannot be adequately understood without reference to the long history of enmity between the Thais on the one hand and the French and the Vietnamese on the other. Siam, as Thailand was then called, was the one country in South East Asia never to have been colonised by a Western power, although during Louis XIV's reign the French almost took over after King Narai made the mistake of inviting them in to check Dutch ambitions. They came and they stayed: French garrisons installed at Bangkok and Mergui only falling to the Siamese after heavy loss of life.