History of Canadian nationality law
Canada established its own nationality law in 1946 with the enactment of the Canadian Citizenship Act 1946, which took effect on 1 January 1947. It was the second nation in the then British Commonwealth to establish its own nationality law; the first was the Irish Free State, which was a Commonwealth member until 1949 and established its own nationality law in 1935.
Under current Canadian law, Canada does not restrict multiple citizenship but Passport Canada encourages its citizens to travel abroad on their Canadian passport, so they can access Canadian consular services.
Under common law, a person born within Her Majesty's dominions became a British subject at birth. The various colonies of the British Empire passed their own laws determining how naturalization as a subject could take place, as well as what status aliens possessed, within their respective jurisdictions. Upon the passage of the Constitution Act, 1867, the Parliament of Canada was given authority over "Naturalization and Aliens", by virtue of section 91(25).
The Aliens and Naturalization Act, 1868 was the first federal Act to be passed, and it provided that persons that had been previously naturalized in any part of the Dominion possessed the same status as anyone naturalized under that Act. In addition:
The 1868 Act was replaced by the Naturalization and Aliens Act, 1881, which came into force on 4 July 1883. It made the rules allowing aliens to hold property uniform throughout the Dominion, and otherwise standardized the law along the same lines as the Naturalization Act 1870 of the United Kingdom.
Canadian citizenship was originally created under the Immigration Act, 1910, which included anyone who was:
Aliens, as well as all other British subjects, who wished to immigrate to Canada required permission to land. "Domicile" was declared to have been acquired by a person having his domicile in Canada for three years after having been landed therein, excluding any time spent in "any penitentiary, jail, reformatory, prison or asylum for the insane in Canada".
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