Abraham Leon (1918–1944) (born Abraham Wejnstok), was a JewishTrotskyist activist and theorist. He was born in Warsaw but his family moved to Belgium where he grew up. Leon became a member and then leader of the Belgian branch of Hashomer Hatzair, a left wing Zionist youth movement. In 1940, after the beginning of World War II, Leon rejected Zionism and became a Trotskyist; around this time he joined the Belgian section of the Fourth International and became an organiser and leader against Nazi occupation and the "militarism" of Winston Churchill, exhorting Belgian workers to fight both Hitler and Churchill in the classical Leninist fashion of turning World War II into civil war. He wrote The Jewish Question: A Marxist Interpretation, a work which remains a widely used Marxist analysis of Jewish socio-economic history.
Leon was arrested by the Nazis in June 1944; he was subsequently deported to Auschwitz where he died of illness in September.