Internment, detention or confinement of a person in time of war. In Canada, such persons were denied certain legal rights, notably habeas corpus, though in certain cases they had the right to appeal their custody. Even if they were not strictly Prisoners of War, civilian internees were generally treated according to international POW standards.

First World War

During the First World War, enemy aliens (nationals of Germany and of the Austro-Hungarian and Turkish empires) were subject to internment, but only if there were "reasonable grounds" to believe they were engaged in espionage or otherwise acting illegally. Some municipalities "unloaded" indigents, many of them recent immigrants, on internment camps.

In 1916–17, many Austrians were paroled to fill labour shortages. Of 8,579 men at 24 camps across Canada, 5,954 were of Austro-Hungarian origin, including 5,000 Ukrainians; 2,009 were Germans; 205 were Turks and 99, Bulgarians. All endured hunger and forced labour, helping to build some of Canada's best-known landmarks, such as Banff National Park. Moreover, 81 women and 156 children, dependants of male internees, were voluntarily interned. Although responsibility shifted in 1915 from the Department of Militia and Defence to the Department of Justice, Major General Sir William Otter remained officer commanding (later director of) internment operations.

Second World War

During the Second World War, the Minister of Justice could detain anyone acting "in any manner prejudicial to the public safety or the safety of the state." Thus both enemy nationals and Canadian citizens were subject to internment. Around 40 camps held an estimated 30,000 to 35,000 prisoners.

Most of the German internees were members of German-sponsored organizations or leaders of the Nazi Party in Canada. Hundreds of Germans on Canadian soil were accused of spying and subversion. The camps also served to house captured enemy soldiers, such as over 700 German sailors captured in East Asia and sent to Canada.

After Italy entered the war, a number of prominent Italians and Canadian fascists, notably Adrien Arcand of Montréal, were interned. Approximately 600 Italian men suspected of sympathizing with fascism were placed into three camps: Kananaskis, Alberta; Petawawa, Ontario; and Fredericton, New Brunswick. This last camp also held 517 Jews sent from England by Winston Churchill, who suspected them of being disloyal.

Immediately after Pearl Harbor the RCMP interned 38 Japanese nationals; later, an additional 720 Japanese, mainly Canadian citizens and members of the Nisei Mass Evacuation Group who resisted separation from their families, were imprisoned. Approximately 20,000 Japanese Canadians were removed from the Pacific Coast in 1942. Many were housed in isolated areas and had their activities severely restricted.

Because citizens could be interned for belonging to outlawed organizations such as the Communist Party, some claimed that internment was used as a weapon against labour leaders, e.g., J.A. "Pat" Sullivan, president of the Canadian Seamen's Union, interned in 1940. Along with about 90 other communists, he was released in 1941 after the Communist-ruled Soviet Union joined the Allies. Most prominent, however, was Mayor Camillien Houde of Montréal, interned four years for denouncing national registration in 1940 as a prelude to conscription.

The army and the Secretary of State shared administrative responsibility for the camps. A total of 26 camps operated in Ontario, Québec, Alberta and New Brunswick, but only two held primarily Canadians. During the First World War, Canada had accommodated 817 internees from Newfoundland and British Caribbean colonies; during the Second World War, Canadian camps housed POWs and merchant seamen captured by the British, as well as some British civilians. At the peak in October 1944, Canada held 34,193 persons for the UK.

Internment in Modern Canada

Provision for internment continued for some time. An emergency planning order approved in May 1981 by Cabinet authorized the Solicitor General to establish civilian internment camps in wartime. However, it was replaced in 1985 by the Emergencies Act, followed by the 1988 Emergency Preparedness Act, the latter of which was repealed in 2007.

Meanwhile, the 1985 Emergencies Act stipulates that "Nothing in this Act shall be construed or applied so as to confer on the Governor in Council the power to make orders or regulations (a) altering the provisions of this Act; or (b) providing for the detention, imprisonment or internment of Canadian citizens or permanent residents within the meaning of subsection 2(1) of the Immigration and Refugee Protection Act on the basis of race, national or ethnic origin, colour, religion, sex, age or mental or physical disability."