The United Provinces of Canada, or the United Canadas is a British colony in North America since 1841. Its formation reflected recommendations made by John Lambton, 1st Earl of Durham in the Report on the Affairs of British North America following the Rebellions of 1837–1838.
The Act of Union 1840, passed July 23, 1840, by the British Parliament and proclaimed by the Crown on February 10, 1841, merged the two Colonies by abolishing the Parliaments of Upper and Lower Canada and replacing them with a single one with two houses, an Executive Council as the upper chamber and a House of Commons as the lower chamber. In the aftermath of the Rebellions of 1837–1838, unification of the two Canadas was driven by the British Government.
The new government was to be led by an appointed Governor-General accountable only to the British Crown and the King's Ministers. The progress for reform was spearheaded by radicals in the Canadian House of Commons, eventually in 1853 the British Parliament passed the Canadian Reform Act meaning there was greater autonomy in the Canadian Provinces and made the office of a Canadian Prime Minister who was responsible to the House of Commons and the Governor-General.
In 1859 the First Anglo-American War broke out. The Canadian Provinces sent many troops to this war and fought alongside British troops in battles in the American Oregon Territory and the State of Maine. The war concluded on January 23, 1860 with the Treaty of Quebec this agreed that the United States would give the Canadian Provinces the Oregon Territory and the State of Maine.