The battalion was formed on 29 December 1941 at Burnham Camp, near Christchurch, under the command of Lieutenant Colonel A. H. L. Sugden, a member of the New Zealand Staff Corps, in response to Japan's entry into the war following the bombing of Pearl Harbor and the invasion of Malaya. With the possibility of a Japanese advance south through the Pacific, the New Zealand Government decided to raise a force of three infantry battalions to bolster the garrison in Fiji. The 37th Battalion was one of these units.