Louis St. Laurent, Canadian lawyer and politician, 12th Prime Minister of Canada (d. 1973)
Louis Stephen St. Laurent (Saint-Laurent or St-Laurent in French, baptized Louis-Étienne St-Laurent; February 1, 1882 – July 25, 1973) was a Canadian lawyer and politician who served as the 12th prime minister of Canada from 1948 to 1957.

Born and raised in southeastern Quebec, St. Laurent was a leading lawyer and a supporter of the Liberal Party of Canada. In February 1942, he entered politics as he won a by-election in the riding of Quebec East and immediately became minister of justice under Prime Minister William Lyon Mackenzie King. In September 1946, St. Laurent became secretary of state for external affairs and served in that post until two years later, when he became leader of the Liberal Party and prime minister, succeeding King who retired. St. Laurent carried the party to back-to-back landslide majority governments in the federal elections of 1949 and 1953.

The second French Canadian to hold the office, St. Laurent strongly advocated against communism, and was an enthusiastic proponent of Canada joining NATO in 1949 to fight the spread of the ideology. His government also contributed troops to the Korean War. At home, St. Laurent's government introduced the registered retirement savings plan (RRSP) and oversaw the construction of the Trans-Canada Highway, St. Lawrence Seaway, and Trans-Canada Pipeline. St. Laurent earned the nickname "Uncle Louis" as he was quite popular among the general public throughout his tenure, and the popularity of his government led many to predict that he'd easily win the 1957 federal election. However, his decision to rush the 1956 debate on the Trans-Canada Pipeline by invoking cloture led some to believe that the Liberals had become arrogant from their two decades in power, and in a major upset, the party was narrowly defeated by John Diefenbaker's Progressive Conservatives, ending nearly 22 years of Liberal rule. Shortly after his defeat, St. Laurent retired from politics and returned back to his law practice. He is ranked highly among analysts and the public, not least because of his progressive programs and fiscally responsible policies that helped shape post-war Canada. According to historian Donald Creighton, he was an "eminently moderate, cautious...man...and a strong Canadian nationalist."