From the 1920s into the 1950s, the Communist Party USA was the most dynamic sector of the American left, and Jewish women—especially Yiddish-speaking immigrants and their American-born daughters—were a major force within the party and its affiliated organizations. Their numbers included community organizers, labor activists, students, artists and intellectuals. When the communist movement faded in the 1950s, these women carried radical traditions into new movements for social justice and international cooperation.