René Lévesque

René Lévesque, the charismatic former journalist and Quebec Liberal cabinet minister, had become increasingly convinced that Quebec needed sovereignty to protect its language, culture, and economic interests. After unsuccessfully pushing the Liberal Party to adopt a "sovereignty-association" position at the October 1967 party convention, Lévesque walked out of the convention hall and left the party. He had served as a transformative Minister of Natural Resources under Jean Lesage, nationalizing Quebec's hydroelectric companies and co-founding the Quiet Revolution. His departure from the Liberals was the political earthquake that launched the modern Quebec sovereignty movement.

Lévesque founded the Mouvement Souveraineté-Association in November 1967, which merged with the Ralliement national in 1968 to create the Parti Québécois. He led the PQ to a historic victory in 1976, becoming Premier of Quebec. His government passed the landmark Bill 101 (Charter of the French Language), held the 1980 sovereignty referendum, and fundamentally transformed Quebec society. Though the referendum was lost 60-40, Lévesque remains one of the most consequential political figures in Canadian history. His departure from the Liberals is arguably the single most important floor crossing in Canadian political history.