Taking the name Radek from a character in a Stefan Żeromski novel, this revolutionary operated across borders to spread communist ideology. Moving from his birthplace of Lviv to activist circles in Germany and eventually the Soviet Union, he served as a central figure in international movements, journalism, and political negotiations before perishing in a labour camp during the Great Purge.
Political Origins and European Exile
Born Karol Sobelsohn, he joined the Social Democracy of the Kingdom of Poland and Lithuania in 1904. Following his involvement in the 1905 Russian Revolution, he fled to Germany. There, he worked for the Social Democratic Party, contributing to publications like Leipziger Volkszeitung. A controversial 1910 accusation of theft, which his allies Rosa Luxemburg and Leo Jogiches initially refuted, eventually led to his expulsion from the party, complicating his status among international social democrats.
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During World War I, he resided in Switzerland, acting as a critical link between Vladimir Lenin and the Bremen Left. He participated in the 1915 Zimmerwald Conference. His political analysis often diverged from his peers; for example, he criticized the 1916 Irish Easter Rising as a petit-bourgeois movement. After the 1917 February Revolution, he supported the transit of Bolshevik leaders back to Russia, though he initially faced entry restrictions himself, instead managing propaganda efforts from Stockholm.
Soviet Power and Comintern Influence
Following the October Revolution, he entered Russia and assumed the role of Vice-Commissar for Foreign Affairs, participating in the Treaty of Brest-Litovsk negotiations. He later focused on activities within the Communist International and taught at Moscow Sun Yat-sen University between 1925 and 1927. His career faced significant reversals due to his alignment with Leon Trotsky against Joseph Stalin, resulting in his temporary expulsion from the Communist Party.
Trial and Final Years
Despite recanting his political stances and gaining readmission to the party, he became a target during the Soviet Great Purge. In 1937, he served as a chief defendant in the Second Moscow Trial. Convicted of treason, he received a ten-year sentence for penal labour. He died in 1939 at the Verkhneuralsk Political Isolator, a facility in the Ural mountains.
Fast facts
- Born: 1885, Lviv
- Died: 1939, Verkhneuralsk
- Education: Jagiellonian University
- Known Languages: German, Polish, Russian, Yiddish
- Primary Employers: Moscow Sun Yat-sen University, Communist International
- Political Affiliation: Communist Party of the Soviet Union
Questions readers ask
What was his original name?
He was born Karol Sobelsohn.
Did he play a role in the Treaty of Brest-Litovsk?
Yes, he served as Vice-Commissar for Foreign Affairs and participated in the negotiations.



