 The Japanese invasion of Burma began in January 1942, and Japan conducted a series of air raids over Rangoon, where the headquarters of the Burma Corps of the British Indian Army was located.To relieve Allied positions in Burma, the Chinese Expeditionary Force (CEF) was formed from the Fifth Army and the New Sixth Army, under the command of American Lieutenant General Joseph Stilwell.The CEF entered Burma in February 1942 and engaged with the Imperial Japanese Army at the Toungoo.