Book excerpt: International Communism and the Spanish Civil War provides an intimate picture of international communism in the Stalin era. Exploring the transnational exchanges that occurred in Soviet-structured spaces - from clandestine schools for training international revolutionaries in Moscow to the International Brigades in Spain - the book uncovers complex webs of interaction, at once personal and political, that linked international communists to one another and the Soviet Union. The Spanish Civil War, which coincided with the great purges in the Soviet Union, stands at the center of this grassroots history. For many international communists, the war came to define both their life histories and political commitments. In telling their individual stories, the book calls attention to a central paradox of Stalinism - the simultaneous celebration and suspicion of transnational interactions - and illuminates the appeal of a cause that promised solidarity even as it practiced terror.