Critical responses to Holocaust denier David Irving have changed dramatically as Irving, a writer on the subject of World War II and Nazism, changed his own public political views; further, there are doubts as to how far Irving applies the historical method. This article documents some of these critical responses over the course of his writing career. Overview Irving was once held in regard for his expert knowledge of German military archives. Much of his scholarship was disputed by historians to the point that his standing as a historian was challenged from his earliest publications. Beginning in the 1970s, Irving began to claim that Hitler had neither ordered the extermination of the Jews nor known about the Holocaust. Contentious in large part for advancing interpretations of the war considered favourable to the German side and for association with far-right groups that advanced these views, by 1988 he began advocating the view that the Holocaust did not take place as a systematic and deliberate genocide, and quickly grew to be one of the most prominent advocates of Holocaust denial, costing him what scholarly reputation he had outside those circles. A marked change in Irving's reputation can be seen in the surveys of the historiography of the Third Reich produced by British historian Ian Kershaw. In the first edition of Kershaw's book The Nazi Dictatorship (1985), Irving was called a "maverick" historian working outside of the mainstream of the historical profession. By the time of the fourth edition of The Nazi Dictatorship in 2000, Irving was described only as a historical writer who had in the 1970s engaged in "provocations" intended to provide an "exculpation of Hitler's role in the Final Solution". Reaction to Irving's work 1960s–1970s In a review of 1977, the British historian Hugh Trevor-Roper wrote that "no praise can be too high for his [Irving's] indefatigable, scholarly industry". Trevor-Roper followed up his praise by expressing severe doubts about Irving's methodology. Trevor-Roper argued that: "He [Irving] seizes on a small, but dubious particle of 'evidence'; builds upon it, by private interpretation, a large general conclusion; and then overlooks or re-interprets the more substantial evidence and probability against it. Since this defective method is invariably used to excuse Hitler or the Nazis and to damage their opponents, we may reasonably speak of a consistent bias, unconsciously distorting the evidence". Finally, Trevor-Roper commented: "When a historian relies mainly on primary sources, which