 A major historiographical debate about the relationship between the German prewar economy and foreign policy decision-making was prompted in the late 1980s, when historian Timothy Mason claimed that an economic crisis had caused a "flight into war" in 1939.Mason argued that the German working-class was opposed to the Nazi dictatorship in the over-heated German economy of the late 1930s.However, Mason’s thesis was opposed by historian Richard Overy who wrote that Germany's economic problems could not explain aggression against Poland and that the reasons for the outbreak of war were due to the ideological choices made by the Nazi leadership.