The Russian Communist leader and publicist Karl Bernardovich Radek (1885-1939) is best known for his brilliant and acerbic polemics. He was an out standing apostle of internationalism.
Karl Radek was born Karl Sobelsohn in Lvov (then in Austrian Poland) to an Austrophile Jewish family. As a youth, he rejected his family's outlook and became involved in political agitation, moving to Switzerland in 1904. There he joined the left wing of Polish socialism, returning to Poland in 1905 to participate in revolutionary activity in Warsaw. After a brief prison term, Radek spent the next decade building his reputation, in both Poland and Germany, as a talented but volatile and often irresponsible journalist. His barbed comments so irritated leading Socialists that he was successively expelled from the Polish and German Socialist parties.
During World War I Radek returned to Switzerland, where he alternately collaborated with and contended with V. I. Lenin in the Zimmerwald Movement, an organization of antiwar Socialists. After the overthrow of the Czar in March 1917, Radek accompanied Lenin in the "sealed train" across Germany, but he was not allowed to enter Russia. He then spent several months in Stockholm organizing Bolshevik support among European Socialists, and after the Bolshevik coup in November 1917 he proceeded to Moscow. There he became responsible for foreign-language propaganda, accompanying Leon Trotsky to Brest Litovsk, where he propagandized German troops. At the end of 1918, after the collapse of the imperial regime in Germany, Radek returned to Berlin in order to help organize the German Communist party. Though he counseled against a German uprising, the "Spartacus" Putsch of January 1919 led to his incarceration for almost a year.
Upon his return to Moscow, Radek was assigned major roles in the Communist International (Comintern), where he enjoyed great influence, particularly in the German Communist party