The Social-Democratic Federation took part in all the political and economic struggles of the English working class; it took pains to bring Socialist views home to them, not only through agitation and propaganda, but also by actions.

Karl Bernhardovic Radek (Russian: Карл Бернга́рдович Ра́дек) (31 October 1885 – 19 May 1939) was a Marxist active in the Polish and German social democratic movements before World War I and an international Communist leader after the Russian Revolution.