1921 in Canada

• March 26 – The Bluenose is launched
• May 28 and 29 – Founding of the Communist Party of Canada at a clandestine meeting held in a barn in Guelph, Ontario.
• June 9 – 1921 Saskatchewan general election: William M. Martin's Liberals win a fifth consecutive majority
• June 15 – Prohibition comes to an end in British Columbia
• July 18 – 1921 Alberta general election: The United Farmers of Alberta (UFA) win a majority, defeating Premier Charles Stewart's Liberals. Henry Wise Wood, who had remained president of the UFA despite opposing its branching into electoral politics, declines the premiership. The UFA caucus hastily selects Herbert Greenfield to become premier.
• July 27 – Frederick Banting and Charles Best discover insulin
• August 13 – Herbert Greenfield becomes premier of Alberta, replacing Charles Stewart
• November 21 – Canada is granted its armorial bearings by Royal Proclamation. Canada's official colours declared to be red and white
• December 6 – Federal election: William Lyon Mackenzie King's Liberals win a minority, defeating Arthur Meighen's Conservatives. Agnes Macphail becomes the first woman elected to Parliament, representing the rural Ontario riding of Grey South East. That election was the first in which all Canadian women (at least 21 years of age) had the right to vote and to stand as candidates. Macphail was re-elected to the House of Commons four times and served for more than eighteen years. Later, she would be one of the first two women elected to the Ontario legislature.[1]
• December 29 – Mackenzie King becomes prime minister, replacing Arthur Meighen.

• February 15 – The Capitol Theatre opened in Winnipeg.
• March 12 – The Capitol Theatre, a lush 2,500 seat movie palace, opened on Vancouver's Granville Street.

• March 24–26 – The Manitoba Junior Hockey League's Winnipeg Falcons win their only Memorial Cup by defeating the Ontario Hockey Association's Stratford Midgets 11 to 9 in a 2-game aggregate played Arena Gardens in Toronto
• April 4 – The Ottawa Senators beat the Vancouver Millionaires 2–1 to win the Stanley Cup[4]
• December 3 – In the first East-West Grey Cup the Toronto Argonauts win their second Grey Cup championship by defeating the Edmonton Eskimos 23 to 0 in the 9th Grey Cup played at Toronto's Varsity Stadium

Arthur Sifton

• January 21 – Arthur Sifton, politician and 2nd Premier of Alberta (b.1858)
• August 29 – Lionel Herbert Clarke, businessman and Lieutenant Governor of Ontario (b.1859)
• October 19 – George Washington Kendall (b.1881)
• November 1 – Zoé Lafontaine, wife of Sir Wilfrid Laurier, 7th Prime Minister of Canada (b.1842)
• November 10 – Jennie Kidd Trout, physician, first woman in Canada legally to become a medical doctor and only woman in Canada licensed to practice medicine until 1880 (b.1841)
• November 27 – Douglas Colin Cameron, politician and Lieutenant-Governor of Manitoba (b.1854)

• List of Canadian films

Frederick Banting speaks on his research into separating life-saving insulin from pancreas's insulin-destoying secretion[5]

Former Indian agent says Kainai (Blood Indians) cheated out of their land by "predatory leases" [6]

Witness testifies before House committee on proportional representation so that MPs "may represent the opinions of people rather than acres" [7]

Prime Minister Meighen rebuffs Opposition Leader Mackenzie King's attempt to advise on upcoming Imperial Conference [8]

Prime Minister Meighen on unity in diversity in Commonwealth of Nations [9]

Nellie McClung says movies are moral menace [10]

Police reject pleas to bust exposed knees [11]

Christmas celebration at rural Prairie school [12]

Franklin D. Roosevelt's family cottage on Campobello Island, N.B., preserved to last year he stayed there [13]