Between 1915 and 1946, the Canadian government put some ten thousand unskilled foreigners, jobless and homeless people, conscientious objectors, perceived enemies of the state, and prisoners of war to work in western Canada's national parks. These men had committed no crimes, but because of war or depression, they were seen as a possible threat to public order and a potential source of civil unrest. Many of the Banff, Jasper, and other...