This accessible text provides a comprehensive narrative and interpretative account of the entire history of the Communist International, 1919-1943. By incorporating the most recent Western and Soviet research the authors explain the legendary complexities of Comintern history and chart its degeneration from a revolutionary internationalist organisation into an obedient instrument of Soviet foreign policy. Key themes include: continuities and discontinuities between the Leninist and Stalinist phases, Bolshevisation versus national traditions, and the role of leading individuals in the Comintern apparatus. A selection of documents will elucidate these central themes.