This article aims to construct an overall image of the concentration and disarmament of Japanese soldiers in Thailand after World War II and analyze its impact. Japanese soldiers in Thailand—a total of about 120,000 at the end of the war—were assigned to 11 concentration camps after the arrival of the Allies at the beginning of September 1945, followed by five concentration camps in November. However, the soldiers’ transfer to the second set of camps was not completed by the end of 1945 since movement from the North stagnated. Disarmament was carried out in the first set of concentration camps, with the disarmed Japanese soldiers coming under the control of the Thai army. The Thai army was garrisoned at the concentration camps, which it secured.

The concentration and disarmament of Japanese soldiers caused several problems in terms of transportation, lodging, and theft. The efficiency of the Thai railways was reduced by air raids during the war, which resulted in delays in the return of Thai soldiers from the North since priority was given to the movement of Japanese soldiers and supplies. Although the lodgings in the camps were constructed by Japanese soldiers, Thais had to procure construction materials and construct lodgings for Thai soldiers at the camps. The Japanese army’s abundant supplies and arms in the camps and dumps resulted in frequent thefts and robberies, some of them involving Thai soldiers.