The following working paper was presented to the Toronto conference of Historical Materialism on May 16, 2010. For Spanish-language translation, see IPS blog de debate. When we celebrate International Women’s Day, we often refer to its origins in U.S. labour struggles early in the last century. Less often mentioned, however, how it was relaunched and popularized in the 1920s by the Communist Women’s Movement. Moreover, this movement itself has been almost forgotten, as have most of its central leaders.