May 1937 saw the defeat of one of the most advanced revolutions in modern history. In Insurrection, Agustín Guillamón explains how and why it happened. One of the foremost historians of the Spanish Civil War writing today, Guillamón is known for his skill at unearthing new information, which he gathers from both archives and interviews. In this, his most recent and newly translated book, he uses that information to shed light on some of the most vexing and previously unanswered questions about the conflict, especially on the way that Stalinist and Republican forces conspired through assassination, intrigue and violence, to suppress the uprising. This is a story that George Orwel recounted, but failed to fully understand, in Homage to Catalonia.