An electoral district in Canada, also known as a constituency or a riding, is a geographically-based constituency upon which Canada's representative democracy is based. It is officially known in Canadian French as a circonscription, but frequently called a comté (county).
Federal electoral districts each return one Member of Parliament (MP) to the Canadian House of Commons; provincial or territorial electoral districts each return one representative — called, depending on the province or territory, Member of the Legislative Assembly (MLA), Member of the National Assembly (MNA), Member of Provincial Parliament (MPP) or Member of the House of Assembly (MHA) — to the provincial or territorial legislature.
While electoral districts in Canada are now exclusively single-member districts, in the past, multiple-member districts were used at both the federal and provincial levels. Alberta had a few districts in its history that returned from two up to seven members: see Calgary, Edmonton and Medicine Hat. British Columbia had a mix of multiple-member districts in Vancouver and single-member districts elsewhere until the 1991 election, and Prince Edward Island had dual-member districts until the 1996 election.
As of June 28, 2004, there were 308 federal electoral districts across Canada. Provinces will sometimes follow similar boundaries for their own provincial ridings — however, this is not always the case, nor is it required. The only province which currently does so is Ontario — at present, electoral districts in the Southern Ontario region use the same boundaries as their current federal counterparts following the 2004 boundary adjustment, while seats in the Northern Ontario region correspond to the federal districts that were in place before the 2004 adjustment. All other provinces have completely different federal and provincial ridings. Ontario also had separate provincial ridings prior to 1999.
Elections Canada is the independent body set up by parliament to oversee Canadian federal elections.
Originally, most electoral districts were equivalent to the counties used for local government, hence the French unofficial term comté. However, it became common, especially in Ontario, to divide counties with sufficient population to multiple electoral divisions; these became unofficially known as ridings, from an archaic British term denoting a subdivision of a county.
Soon after Confederation, the urban population grew — and more importantly, most city dwellers gained the franchise after property ownership was no longer required to gain the vote. Rural constituencies therefore became geographically larger through the 20th century and generally encompassed one or more counties each, and the word "riding" was then used to refer to any electoral division.
A political party's local organization is generally known as a riding association.
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