The 13th Canadian Parliament was in session from March 18, 1918, until October 4, 1921. The membership was set by the 1917 federal election on December 17, 1917, and it changed only somewhat due to resignations and by-elections until it was dissolved prior to the 1921 election.

The 1917 Canadian federal election was held on December 17, 1917, to elect members of the House of Commons of Canada of the 13th Parliament of Canada. Described by historian Michael Bliss as the "most bitter election in Canadian history", it was fought mainly over the issue of conscription. The election resulted in Prime Minister Sir Robert Borden's Unionist government elected with a strong majority and the largest percentage of the popular vote for any party in Canadian history.