Born Oct. 19, 1862, in Bonnières, Seine-et-Oise Department; died Sept. 5, 1922, in Chamonix-Mont-Blanc, Haute-Savoie Department. Figure in the French workers’ movement.
Sembat was a member of an organization of Blanquists and a contributor to socialist and radical left publications. From 1893 to 1922 he was a parliamentary deputy. After the formation of the United Socialist Party of France (SFIO) in 1905, he became one of the leaders of the party’s reformist wing. During World War I, Sembat maintained a social-chauvinist position; he served as minister of public works from 1914 to 1916. In 1919 and 1920, Sembat opposed the union of the SFIO with the Comintern; he was responsible in part for the split that occurred at the party’s congress in Tours in December 1920.