With potential new Commonwealth immigrants who did not already owe allegiance to Canada's shared sovereign, the Parliament of Canada thus enacted the Canadian Citizenship Act 1946, which came into effect on 1 January of the following year. New immigrants were then required to recite the Oath of Allegiance for Purposes of Citizenship, which was an adaptation of the original Oath of Allegiance: ""I swear that I will be faithful and bear true allegiance to His Majesty King George the Sixth, His Heirs and Successors, according to law, and that I will faithfully observe the laws of Canada and fulfil my duties as a Canadian citizen""; Prime Minister William Lyon Mackenzie King was the first person to take this oath. Though new citizens were thereafter required by law to recite the Oath of Citizenship, on 1 April 1949, 359,000 Newfoundlanders became Canadian citizens without taking the oath, when the British crown colony joined Canadian Confederation.