Alfred Rosmer (1877–1964) was a syndicalist leader before World War I and one of the few leaders of that movement to oppose the war from a revolutionary internationalist position. A friendship with Leon Trotsky dated from that period, when the latter was living in France. After the war he became a leading figure in the Communist Party of France before being ousted as early as 1924, along with Boris Souvarine and Pierre Monatte, for opposing Stalinism. He then became a leader of the early Trotskyist movement until he dropped out of politics in 1932.