Almost two months after the resounding defeat of the Nazis in Stalingrad, on 13 April 1943, a mass grave of Polish POWs was found in the Katyn Forrest, a few miles away from Smolensk. Under the guidance of Goebbels, the blame was cast against the Soviet leadership and this falsehood was eagerly adopted by the imperialists and bourgeois historiography in Europe and the United States.