On January 17, 1941, French colonial naval forces engaged the naval forces of Siam (Thailand after 1948) during the Franco-Thai War, a smaller war within the larger conflagration that was World War II. The French soundly defeated the Thai force, leading to negotiations and an end to the War via a Japanese brokered ceasefire on January 31, 1941.
Digging Deeper
Prior to World War II, the French colony of French Indochina (mainly what is now Vietnam, Cambodia and Laos) included land claimed by Thailand. (The Thai people always called their country the English equivalent of “Thailand,” while outsiders called the country Siam until 1948-1949.) Once the French were invaded by the Germans and defeated in 1940, the government of France was split between Occupied France and an autonomous puppet state of Germany called Vichy France. The government of Vichy France had nominal control of French colonies, but had little practical ability to administer or defend the overseas territories such as French Indochina.
