Approximately 8,000 Canadian civilians were imprisoned during the First World War because of their ethnic ties to Germany, Austria-Hungary, and other enemy nations. Although not as well-known as the later internments of Japanese Canadians during the Second World War, these incarcerations played a crucial role in shaping debates about Canadian citizenship, diversity, and loyalty. Tracing the evolution and consequences of Canadian government policy towards immigrants of enemy nationality, No Free Man is a nuanced work that acknowledges both the challenges faced by the Government of Canada as well as the experiences of internees and their families.