 The 5th Infantry was posted at Camp Paraiso, Panama Canal Zone from 1939–1943.It had previously been posted at Fort Williams, Maine, where it was nominally assigned to the inactive 9th Infantry Division.With the onset of World War II, the 5th Infantry was made a part of the 71st Infantry Division and participated in an experiment to develop a "light" infantry division, capable of operating in harsh terrain from the mountains to the desert.