Taking advantage of the German occupation of France in early World War II, Thailand used military force and diplomatic maneuvering to seize some of the territory it had ceded to French Indochina in 1893 and 1907.
Situated between French and British colonial possessions in Southeast Asia, Siam as Thailand was known before 1939 had long sought the return of territories it had traded in return for continued independence at the turn of the century. Taking advantage of the weakness of French Indochina following the defeat of France by Nazi Germany in 1940, Thailand used military force and Japanese diplomatic support to recover some bordering provinces, before Japan took control of Indochina
For several centuries, Cambodia had been a tributary of Siam. In 1867, France absorbed most of Cambodia as a protectorate and incorporated it into its Indochinese colony. Siam retained the western Cambodian provinces of Battambang and Siem Reap. In April of 1893, fighting between French and Siamese forces in Laos led the French to send gunboats up the Chao Phraya River, blockading the Siamese capital city of Bangkok (Krung Thep). As a result of the so-called Crisis of 1893, King Chulalongkorn (Rama V) of Siam agreed to pay a sizable indemnity to France and to cede part of Luang Prabang province in Laos in order to preserve the core of his kingdom. France, however, claimed that it had inherited the old Vietnamese right to rule over all of Cambodia and Laos, and in 1907, France seized the remaining part of Luang Prabang, as well as Battambang and Siem Reap, incorporating them into French Indochina, which then included Vietnam, Cambodia, and Laos.
During the late 1930’s, Siam began to press France for a return of the areas of Laos west of the Mekong River. Thai prime minister Luang Phibunsongkhram attempted to emulate the rule of the militarists in control of the Japanese government. His picture became omnipresent, while he also instituted a regime of repression against the Chinese minority in Thailand. Phibunsongkhram sought to use the issue of lost territories to bolster his reputation as a strong leader and to right an old grievance long resented by the Thais. One of his long-term goals was to fulfill the ambition of many Thais of creating a greater Thailand by absorbing provinces outside Thailand that had an ethnic Thai population. Thailand increasingly adopted a bellicose tone over its “lost” territories.
Following the defeat of France by Nazi Germany in June, 1940, the section of France not under direct German control and all French colonial possessions were governed by a weak government established in the French city of Vichy.
Anti-French
In early January, 1941, Thai warplanes began making daytime attacks on Vientiane, in Laos, and Battambang and Sisophon, in Cambodia. The French retaliated. The Thai Burapha (eastern) and Isaan (northeastern) armies then launched a series of border attacks against French Indochina, which grew into a small war. French forces were outnumbered, lacked adequate supplies, and had little intelligence on the disposition of Thai forces. The Thais quickly consolidated their hold on Laotian areas, but found more difficulties in Cambodia. Early on January 16, the French launched a large but poorly coordinated counterattack on Thai forces at Yang Dang Khum and Phum Preav, in Cambodia, where they were repelled with heavy casualties. However, Thai armored forces were unable to follow up their successful defense with a decisive defeat of the retreating French as a result of effective French artillery.
While generally triumphant on land, Thai naval forces found less success against the French. On January 17, the French light cruiser Lamotte-Piquet caught a small Thai naval force near the island of Koh Chang, in the Gulf of Thailand near the border. The French ship sank the Thai coastal defense ship Thonburi. This minor naval action was the only notable French success in the war. On January 24, Thai warplanes struck a French airfield near Angkor and inflicted more humiliation on the French. At this juncture, Phibunsongkhram asked for Japanese intervention, and a general armistice was declared on January 28. On March 11, 1941, after difficult negotiations in Tokyo, France gave up control of almost all of Laos west of the Mekong River and two western Cambodian provinces.
The short war soured what remained of Thailand’s relations with the United States. The United States reacted in part by cutting off exports of oil. The British, more concerned with maintaining good relations with Thailand, in part to protect their colonies in Malaya and Burma, acquiesced. Thailand quickly integrated the conquered territories into the Thai national structure. With the territories under Thai control, the prime minister sought to distance Thailand from Japan and improve relations with the British and the United States.
In the days following the Japanese attack on Pearl Harbor, which brought the United States into the war against Japan, the Japanese army invaded Thailand. After putting up a sharp but futile defense, the Thai army allowed the Japanese to enter Thailand and use Thai territory in their war against British Malay and Burma. Phibunsongkhram had been away from Bangkok when the Japanese invaded, but he quickly acquiesced once he returned to the capital. Although no hard evidence exists, the suspicion remains that his convenient absence from Bangkok and the initial fighting was a deliberate ploy to give himself political coverage.
In 1943, Thailand invaded and annexed the Shan states from the British colony of Burma, which was then under Japanese control. Japan also gave Thailand control of four northern Malay states that it had lost to Great Britain in the early twentieth century. Following the end of World War II, Thailand quickly withdrew any claims to areas it had taken from Burma and Malay, but it desperately wanted to retain the territories taken from Laos and Cambodia. Residents of the newly acquired territories voted in national elections in January and August of 1946. However, Thailand also sought a role in the emerging international order, the cornerstone of which was membership in the United Nations. In return for France dropping its threat to veto Thailand’s entrance into the international body, Prime Minister Pridi Phanomyong, who had been active in the anti-Japanese Free Thai movement during the war, took the more pragmatic course and ceded the territories back to the French.
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Haseman, John B. The Thai Resistance Movement During World War II. Chiang Mai, Thailand: Silkworm Books, 2002. An outsider’s perspective on the short yet sharp fighting between Japanese forces and Thai forces two hours after the attack on Pearl Harbor and the underground resistance movement that sprang up in its aftermath. -
Reynolds, E. Bruce. Thailand and Japan’s Southern Advance, 1940-1945. New York: St. Martin’s Press, 1994. Nuanced account of the extremely complicated relationship between Thailand and Japan during World War II. Written predominantly from the Thai point of view, it shows that Thai leaders sought to gain whatever advantage the nation could through the instability in the Far East, but above all desired to keep Thailand independent. -
Tejapira, Kasian. Commodifying Marxism: The Formation of Modern Thai Radical Culture, 1927-1958. Kyoto, Japan: Kyoto University Press, 2003. A history of Marxism in Thailand, mainly from the end of the absolute monarchy in the 1930’s through the end of the 1950’s. -
Wyatt, David K. Thailand: A Short History. New Haven, Conn.: Yale University Press, 1982. Standard scholarly account of Thai history from the ancient period until the end of the twentieth century.
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