The history of Arizona during World War II begins in 1940, when the United States government began constructing military bases within the state in preparation for war. Arizona's contribution to the Allied war effort was significant both in terms of manpower and facilities supported in the state. Prisoner of war camps were operated at Camp Florence and Papago Park, and there was an internment camp to house Japanese-Americans, most of them citizens, who had been forcibly deported from the West Coast.