Clara Zetkin ( `` née '' Eissner ; 5 July 1857 -- 20 June 1933 ) was a German Marxist theorist , activist , and advocate for women 's rights .
Clara Josephine Zetkin ( born `` Clara Josephine Eissner '' ; 5 July 1857 - 20 June 1933 ) was a German Marxist theorist and advocate for women 's rights .