After the “exposure of the cult of personality,” one of the main reasons for the disaster of 1941 is considered to be mass repressions against the command staff of the Red Army, which “bled the Red Army on the eve of the war.” However, in recent years, this thesis has increasingly been questioned - according to Stalinist historians, the “cleansing” of enemies of the people and conspirators only benefited the country: without this cruel but necessary measure, the Red Army supposedly had no chance of defeating the previously invincible Wehrmacht. Is there at least some truth in these judgments? What exactly happened to the Red Army in 1937–1938? What provoked the orgy of arrests and executions? Is the “military conspiracy” hypothesis confirmed? What was the true scale of the repression? And most importantly, how much damage did they cause to the combat capability of the Red Army on the eve of the war? This book has answers to all these questions. This fundamental work introduced into scientific circulation a huge array of declassified documents from military and KGB archives and for the first time provided a comprehensive, comprehensive analysis of Stalin’s “purge” of the Red Army. This is the world's first encyclopedia dedicated to the tragedy of the Red Army in 1937–1938. A special merit of the author was the publication of the “Martyrology”, containing information about more than 2000 repressed commanders - from marshal to lieutenant.