Fifteenth Army (Japan)

The Japanese 15th Army was an army of the Imperial Japanese Army during World War II. It was involved in the invasion of Burma in December 1941 and served in that country for most of its war service. The Japanese 15th Army was formed on November 9, 1941, as a component of the Southern Expeditionary Army Group for the specific task of invading the British colony of Burma. To do this the army, then based in Indo-China, needed to transit through Thailand. On December 8, 1941, the 33rd and 55th Divisions of the army spearheaded by the Imperial Guard invaded Thailand overland from what is now Cambodia. The invasion was supported by landings on the coast to the south of Bangkok by the army's 143rd Infantry Regiment. Fighting lasted only a few hours before the Thai government ceded access. Under Lieutenant General Shōjirō Iida, the IJA 15th Army invaded the southern Burmese province of Tenasserim. The Fifteenth Army consisted initially of the highly regarded 33rd Infantry Division and the 55th Infantry Division. The latter attacked from northern Thailand, which had signed a treaty of friendship with Japan on December 21, 1941. The 15th Army quickly advanced through southern Burma, defeating the British and Indian Burma Army in several engagements, and capturing the capital of Rangoon by March 7, 1942. The Army was reinforced by troops released by the Fall of Singapore and drove northwards into central Burma, defeating the British Burma Corps and the Chinese forces, ultimately driving the Allies from Burma. During the following year, the Army remained as a garrison force in Burma, defeating an Allied offensive in Arakan and inflicting heavy casualties on a long-range penetration raid under Orde Wingate. In 1944, the Fifteenth Army became part of the Burma Area Army. Lieutenant General Iida was posted back to Japan and Lieutenant General Renya Mutaguchi took command. He forcefully advocated an offensive against British India. The offensive, Operation U-Go, was launched in March.