British North America Act, 1867, S. 146
146. It shall be lawful for the Queen, by and with the Advice of Her Majesty’s Most Honourable Privy Council, on Addresses from the Houses of the Parliament of Canada, and from the Houses of the respective Legislatures of the Colonies or Provinces of Newfoundland, Prince Edward Island, and British Columbia, to admit those Colonies or Provinces, or any of them, into the Union, and on Address from the Houses of the Parliament of Canada to admit Rupert’s Land and the North-western Territory, or either of them, into the Union, on such Terms and Conditions in each Case as are in the Addresses expressed and as the Queen thinks fit to approve, subject to the Provisions of this Act; and the Provisions of any Order in Council in that Behalf shall have effect as if they had been enacted by the Parliament of the United Kingdom of Great Britain and Ireland.
[Note: Rupert’s Land and the North-Western Territory (subsequently designated the Northwest Territories) became part of Canada, pursuant to this section and the Rupert’s Land Act, 1868 (No. 6 infra), by the Rupert’s Land and North-Western Territory Order (June 23, 1870) (No. 9 infra).
British Columbia was admitted into the Union pursuant to this section by the British Columbia Terms of Union (May 16, 1871) (No. 10 infra).
Prince Edward Island was admitted into the Union pursuant to this section by the Prince Edward Island Terms of Union (June 26, 1873) (No. 12 infra).
The Provinces of Alberta and Saskatchewan were established, pursuant to the Constitution Act, 1871 (No. 11 infra), by the Alberta Act (July 20, 1905) (No. 20 infra) and the Saskatchewan Act (July 20, 1905) (No. 21 infra) respectively.
Newfoundland was admitted as a province by the Newfoundland Act (March 23, 1949) (No. 32 infra), which confirmed the Agreement containing the Terms of Union between Canada and Newfoundland.
The Yukon Territory was created out of the Northwest Territories in 1898 by The Yukon Territory Act (No. 19 infra).]