The British North America Act, 1840 (3 & 4 Victoria, c.35), also known as the Act of Union 1840, (the Act) was approved by Parliament in July 1840 and proclaimed February 10, 1841, in Montreal. It abolished the legislatures of Lower Canada and Upper Canada and established a new political entity, the Province of Canada to replace them. The Act was similar in nature and in goals to the other Acts of Union enacted by the British Parliament.



The Province of Canada (or the United Province of Canada or the United Canadas) was a British colony in North America from 1841 to 1867. 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 on 23 July 1840 by the British Parliament and proclaimed by the Crown on 10 February 1841, merged the Colonies of Upper Canada and Lower Canada by abolishing their separate parliaments and replacing them with a single one with two houses, a Legislative Council as the upper chamber and the Legislative Assembly as the lower chamber. In the aftermath of the Rebellions of 1837–1838, unification of the two Canadas was driven by two factors. Firstly, Upper Canada was near bankruptcy because it lacked stable tax revenues, and needed the resources of the more populous Lower Canada to fund its internal transportation improvements. Secondly, unification was an attempt to swamp the French vote by giving each of the former provinces the same number of parliamentary seats, despite the larger population of Lower Canada.

Although Durham's report had called for the Union of the Canadas and for responsible government (a government accountable to an independent local legislature), only the first of the two recommendations was implemented in 1841. For the first seven years, the government was led by an appointed governor general accountable only to the British Crown and the Queen's ministers. Responsible government was not achieved until the second LaFontaine–Baldwin ministry in 1849, when Governor General James Bruce, 8th Earl of Elgin, agreed to request a cabinet be formed on the basis of the largest party in the Legislative Assembly, effectively making the premier the head of the government and reducing the governor general to a more symbolic role.

The Province of Canada ceased to exist at Canadian Confederation on 1 July 1867, when it was divided into the Canadian provinces of Ontario and Quebec. Ontario included the area occupied by the pre-1841 British colony of Upper Canada, while Quebec included the area occupied by the pre-1841 British colony of Lower Canada (which had included Labrador until 1809, when Labrador was transferred to the British colony of Newfoundland). Upper Canada was primarily English-speaking, whereas Lower Canada was primarily French-speaking.