The Canadian Citizenship Act, S.C. 1946, c. 15, is an Act of the Parliament of Canada which separated Canadian citizenship from British nationality.
The status of "Canadian citizen" was originally created under the Immigration Act, 1910, to designate those British subjects who were born, naturalized or domiciled in Canada. All other British subjects required permission to land. "Domicile" was defined as having been resident in Canada for three years, excluding any time spent in prisons or mental institutions.
A separate status of "Canadian national" was created under the Canadian Nationals Act, 1921, which was defined as being a Canadian citizen as defined above, their wives, and any children (fathered by such citizens) that had not yet landed in Canada.
However, these concepts were merely subsets of the status of "British subject", which was regulated by the Imperial British Nationality and Status of Aliens Act 1914, which was adopted in Canada by the Naturalization Act, 1914.
Canadian citizenship, as a status separate from British nationality, was created by the Canadian Citizenship Act, 1946, which came into effect on 1 January 1947.
Canadian citizenship was generally conferred immediately on the following persons:a British subject who was born in Canada (and had not become an alien before 1947)
a person other than a natural-born Canadian citizen:
who was granted, or whose name was included in, a certificate of naturalization under any act of the Parliament of Canada and had not become an alien at the commencement of the Act, or
who was a British subject who had acquired Canadian domicile (i.e., five years' residence in Canada as a landed immigrant) before 1947
a British subject who lived in Canada for 20 years immediately before 1947 and was not, on 1 January 1947, under order of deportation
women who were married to a Canadian before 1947 and who entered Canada as a landed immigrant before 1947
children born outside Canada to a Canadian father (or mother, if born out of wedlock) before 1947
In the latter two cases, a "Canadian" was a British subject who would have been considered a Canadian citizen if the 1947 Act had come into force immediately before the marriage or birth (as the case may be).
Where the child born outside Canada was not a minor (i.e., was not under 21 years in age) at the time the Act came into force, proof of landed immigrant status was required to confirm Canadian citizenship.
In addition to those people who became Canadian citizens upon the coming into force of the Act (popularly known as the "1947 Act" due to the year it came into force), citizenship afterwards was generally acquired as follows:birth in Canada (except where either parent is a representative of a foreign government, their employee, or anyone granted diplomatic privileges or immunities AND neither parent is a citizen or permanent resident)
naturalization in Canada after five years' residence as a landed immigrant
grant of citizenship to a foreign woman married to a Canadian man after one year's residence as a landed immigrant
grant of citizenship to women who lost British subject status prior to 1947 upon marriage to a foreign man or his subsequent naturalization
registration of a child born outside Canada to a Canadian "responsible parent" (being the father, if the child was born in wedlock, or the mother, if the child was born out of wedlock and was residing with the mother, if the father was deceased or if custody of the child had been awarded to the mother by court order)
Loss of Canadian citizenship generally occurred in the following cases:naturalization outside Canada
in the case of a minor, naturalization of a parent
service in foreign armed forces
naturalized Canadians who lived outside Canada for 10 years and did not file a declaration of retention
where a Canadian had acquired that status by descent from a Canadian parent, and who was either not lawfully admitted to Canada for permanent residence on the commencement of the Act or was born outside Canada afterwards, loss of citizenship could occur on the person's 22nd birthday unless the person had filed a declaration of retention between their 21st and 22nd birthday and renounced any previous nationality they possessed.
Although Canada restricted dual citizenship between 1947 and 1977, there were some situations where Canadians could nevertheless legally possess another citizenship. For example, migrants becoming Canadian citizens were not asked to formally prove that they had ceased to hold the nationality of their former country. Similarly children born in Canada to non-Canadian parents were not under any obligation to renounce a foreign citizenship they had acquired by descent. Holding a foreign passport did not in itself cause loss of Canadian citizenship.
A notable exception to the 1947 act is the annexation of Newfoundland to Canada in 1949, whereby all native or naturalized Newfoundlanders were granted Canadian citizenship under the laws stated in the citizenship act, upon the date of union on April 1, 1949.
The Act was replaced on 15 February 1977 by the Canadian Citizenship Act, 1976, now known as the Citizenship Act.