The Worker's Friend Group was a Jewish anarchist group active in London's East End in the early 1900s. Associated with the Yiddish-language anarchist newspaper Arbeter Fraint ("Worker's Friend") and centered around the German emigre anarchist Rudolf Rocker, the group ran a social center known as the Worker's Friend Club and Institute and Jubilee Street Club from 1906 to 1915. The club became a fixture in London's Jewish social community and was influential on the area's artists and writers. Its cultural programming included concerts, performances, and lectures on political, scientific, and literary topics. The newspaper, begun as a Jewish socialist periodical, grew towards anarchism with the arrival of Saul Yanovsky. It was the most popular radical Yiddish-language newspaper in London by 1904 and reached a peak circulation at 5,000 weekly copies the next year. The Arbeter Fraint ran from 1885 to 1915. The group's operations declined following the British entry into World War I, as rising anti-German sentiment and Rocker's anti-war beliefs culminated in his detention, never to return to the town.