The First Special Service Force was an elite World War II U.S.-Canadian unit formed in 1942 at the direction of President Roosevelt, General George Marshall, and British leaders Prime Minister Winston Churchill and Lord Mountbatten for parachuting into occupied enemy territory and destroying vital Axis installations. It required a top notch area for special training in mountaineering, skiing, parachuting, demolitions, and weapons, and Fort William H. Harrison west of Helena, Montana, proved ideal. There rugged volunteers from the United States and Canadian armies trained together. The unit chose the crossed arrows of the frontier Army Indian Scouts as its branch insignia and a red spearhead for its shoulder patch. Combat casualties were high, but the force never failed a mission. Called "The Black Devils" by the Germans, it became legendary for ferocious nighttime fighting, and its legacy lives on today in the Special Forces of both countries.