 Spence, who had been a journalist and had served in the Militia before the war, volunteered for overseas duty with the Second Australian Imperial Force on 25 June 1940, at Miowera, Queensland.A major, he was originally posted to the 2/26th Battalion, but was posted away from the unit to the commandos before the battalion embarked on its ill-fated deployment to Singapore.He was later appointed commander of the 2/2nd Independent Company, a commando unit, and went with it as part of Sparrow Force to Dutch Timor in 1941.