1957 Canadian federal election in the context of Louis St. Laurent

The Progressive Conservative Party of Canada (PC; French: Parti progressiste-conservateur du Canada) was a centre to centre-right federal political party in Canada that existed from 1942 to 2003.

From Canadian Confederation in 1867 until 1942, the original Conservative Party of Canada participated in numerous governments and had multiple names. In 1942, its name was changed to the Progressive Conservative Party under the request of newly elected party leader Premier John Bracken of Manitoba, a former member of the Progressive Party of Manitoba. In the 1957 federal election, John Diefenbaker carried the party to their first victory in 27 years and the following year, led the party to the largest federal electoral landslide in history. During his tenure, human rights initiatives were achieved, most notably the Bill of Rights. In the 1963 federal election, the party lost power and would not regain it until 1979, when Joe Clark led the party to a minority government victory. The party lost power just nine months later and in 1983, Clark lost his leadership role to Brian Mulroney, who helped the PC Party gain popularity in Quebec. Mulroney won back-to-back majority governments in 1984 and 1988, and during his tenure, major economic reforms such as the North American Free Trade Agreement and the goods and services tax (GST) were introduced.

Lester Bowles Pearson (23 April 1897 – 27 December 1972) was a Canadian politician, diplomat, and scholar who served as the 14th prime minister of Canada from 1963 to 1968. He also served as leader of the Liberal Party from 1958 to 1968 and as leader of the Official Opposition from 1958 to 1963.

Born in Newtonbrook, Ontario (now part of Toronto), Pearson pursued a career in the Department of External Affairs went on to serve as the Canadian ambassador to the United States from 1944 to 1946. He entered politics in 1948 as Secretary of State for External Affairs, serving in that position until 1957 in the governments of William Lyon Mackenzie King and Louis St. Laurent. Pearson was also the seventh president of the United Nations General Assembly from 1952 to 1953. He was a candidate to become secretary-general of the United Nations in 1953, but was vetoed by the Soviet Union. He later won the Nobel Peace Prize in 1957 for organizing the United Nations Emergency Force to resolve the Suez Crisis, for which he received worldwide attention. After the Liberal Party was defeated in the 1957 federal election, Pearson handily won the leadership of the party in 1958. He suffered two consecutive defeats by Progressive Conservative prime minister John Diefenbaker in 1958 and 1962. He successfully challenged Diefenbaker for a third time in the 1963 federal election, winning a minority government. Pearson's Liberals won another minority government in the 1965 federal election.

The 1958 Canadian federal election was held to elect members of the House of Commons of Canada of the 24th Parliament of Canada on March 31, 1958, just nine months after the 23rd election. It transformed Prime Minister John Diefenbaker's minority into the largest majority government in Canadian history and the second-largest percentage of the popular vote; only Unionist Prime Minister Robert Borden’s triumph in the 1917 federal election, at 56.93 percent, was higher. Although the Tories would surpass their 1958-seat total in the 1984 election, the 1958 result (achieved in a smaller House) remains unmatched both in terms of percentage of seats (78.5%) and the size of the government majority over all opposition parties (a 151-seat majority). Voter turnout was 79.4%, the highest percentage of eligible electors to cast a ballot in Canadian federal election history.