On June 22, 1941, Nazi Germany invaded the Soviet Union in Operation Barbarossa despite the non-aggression treaty between the two powers known as the Ribbentrop-Molotov Pact of August 1939. Historians have generally agreed this invasion is the major turning point in World War II in the European theater. However, historians have disagreed on the actual perspective and awareness level of the Soviet Union's leadership, particularly Joseph Stalin, on the eve of Operation Barbarossa. Several interpretations have been developed on Stalin's knowledge of Operation Barbarossa over the decades since World War II. This study examines competing explanations for the poor performance of the Soviet leadership and the Soviet Army during the early stages of Operation Barbarossa to compare and contrast the strengths and weaknesses of each and identify the current state of research, so an informed judgment can be offered on which offers the most accurate, reliable assessment. Based on this extensive literature review of these different interpretations, Gorodetsky's School is the most cogent and sound because of having access to recently released Soviet era archival material.