A courageous and well-documented analysis of violence in the Republican rear during the Spanish Civil War. Francisco Núñez Roldán presents the extrajudicial crimes, religious persecution, and systematic destruction of artistic and cultural heritage that took place in the area controlled by the Popular Front. This meticulous investigation covers episodes such as the "death trains," the Checas of Madrid, the Paracuellos massacre, and the systematic religious persecution that claimed nearly 7,000 victims among priests and religious figures. The author accurately documents how the mechanisms of revolutionary terror operated in both Castile, Levante, Catalonia, and Andalusia, where places such as Malaga became veritable laboratories of political violence. He studies the Republican bombing of civilian populations, labor camps such as Turón, and the numerous mass graves and mine shafts where the victims were thrown. Particularly revealing is his analysis of the destruction of artistic heritage, showing how vandalism against churches and monuments was not accidental but an integral part of a revolutionary project. The book reveals the ideological origins of this violence, linking it to the guidelines of the Communist International and the implementation of the Soviet model. It dismantles the simplified view of an idyllic Republic cut short by rebel soldiers, showing how, from 1931 onwards, an atmosphere of intolerance developed that would culminate in war. "A necessary work for understanding the complex panorama of that national tragedy. Only a complete knowledge of the past, without ideological omissions, can help us build a future of genuine reconciliation." From the prologue by Pedro de Tena