III Corps was an Australian Army unit during World War II. It was responsible for the defence of Western Australia in 1942-45. The founding unit of the corps was a West Australian-formed Militia unit, the 13th Brigade. In mid-1942, as fears of Japanese surface attacks against the Australian mainland were increasing, the 4th Division, a Militia division raised in Victoria, was included and Major General Gordon Bennett was appointed corps commander. In August 1942, the 2nd Division, a New South Wales Militia unit joined III Corps. According to the Army History Unit: