Canada has ten provinces and three territories that are sub-national administrative divisions under the jurisdiction of the Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North America—New Brunswick, Nova Scotia, and the Province of Canada (which upon Confederation was divided into Ontario and Quebec)—united to form a federation, becoming a fully independent country over the next century. Over its history, Canada's international borders have changed several times as it has added territories and provinces, making it the world's second-largest country by area.
The major difference between a Canadian province and a territory is that provinces receive their power and authority from the Constitution Act, 1867 (formerly called the British North America Act, 1867). Territories are federal territories whose territorial governments have powers delegated to them by the Parliament of Canada. Powers are divided between the Government of Canada (the federal government) and the provincial governments by the Constitution Act, either exclusively or concurrently. A change to the division of powers between the federal government and the provinces requires a constitutional amendment. A similar change affecting the territories can be performed unilaterally by the government or Parliament of Canada.