An objective and documentary history of the earliest origins and formative years of the Workers-Peasants Red Army from the Civil War to the initial disasters of the war with Germany, the Great Patriotic War, culminating in the "battle for Moscow" in November-December 1941. The study makes extensive use of Soviet military histories, specialist military monograhs, Red Army regulations, military manuals and handbooks, memoirs, documentary collections on Soviet military organization and Army-Party relations. Unpublished captured German military documents describe the secret Red Army-Reichswehr collaboration. Japanese Army records provide detailed information on the Soviet military build-up in the Far East. The "Tukhachevskii Affair" is investigated together with Stalin's murderous military purge and its consequences for the Red Army. Poor Soviet performance in the "Winter War" with Finland prompted hasty reforms, but neither reorganization nor rearmament was complete before the German invasion in June 1941. First suffering catastrophic loss inflicted by the Wehrmacht, the Red Army had recovered sufficiently by December 1941 to defend Moscow and to counter-attack.