At meetings across the country on Holocaust Memorial Day, worthies intoned the “lessons of the Holocaust” and warned that we must “learn from the past”. But ask most historians and they will blanche at the thought of anything as static or as simple as “lessons”. Over the past five decades, “Holocaust studies” have altered almost beyond recognition and explanations for what occurred have changed significantly.

In the 1950s, most people regarded the Third Reich as a criminal regime that had been run by crazed sadists. Nazi anti-Semitism, it was thought, had been a device to distract the masses. And it was widely believed that few Germans or inhabitants of conquered countries had sympathised with the assault on the Jews. As for the Jews themselves, they had gone to the gas chambers like lambs to the slaughter.

This narrative was both a legacy of the Nuremberg trials and a convenient fiction used to justify Cold War alliances and enmities. At Nuremberg, the surviving “top Nazis” took the fall for the crimes of the regime. Former Axis powers or belligerents now within the Nato fold were presented as having been unwilling or unwitting accomplices of the Nazis.

The first crack in this facade came with the trial of Adolf Eichmann in Jerusalem in 1961- 62. The Israeli authorities orchestrated the hearings to present every dimension of Jewish life under Nazi rule, with the emphasis on forms of resistance. They arranged for Nazi collaboration to be exposed, while “bystanders”, particularly the Allied powers and the Vatican, were shamed by evidence of their inaction.

However, the impact of the trial was shaped most decisively by the reporting of Hannah Arendt, who wrote about it for the New Yorker. She saw in Eichmann a living vindication of her earlier analysis of totalitarianism. His unthinking obedience was the reflex of totalitarian man, the “banality of evil”. Arendt’s (erroneous) description of Eichmann’s character irritated historians who detected rather more ideology and animosity in his conduct. And she provoked outrage with her claim that the Jewish leadership had colluded in their own destruction.

This allegation was strongly influenced by Raul Hilberg’s monumental study The Destruction of the European Jews (1961). Hilberg, whose Jewish family had fled Austria after the Anschluss, disparaged survivor testimony and drew almost exclusively on German documentation. But in the German record the Jews were always portrayed as outwitted and complaisant. Consequently, Hilberg’s work generated the impression of a bureaucratic machine that crushed hapless, silent victims.

The controversy that Hilberg’s book aroused marked the birth of what today we call “Holocaust studies”. Yad Vashem in Jerusalem, Israel’s official Holocaust memorial and museum, became an engine of research. During the 1970s and 1980s, Isaiah Trunk, Israel Gutman, Shmuel Krakowski, Dov Levin and Yitzhak Arad, all of whom had endured the ghettos and the camps, or else had fought as partisans, published histories of Jewish life under Nazi rule, with an emphasis on eastern Europe and varieties of resistance. The stereotype of Jews passively accepting their fate was shattered forever.

Meanwhile, German scholarship (mainly in West Germany) was galvanised by the trial of Auschwitz personnel that began in Frankfurt in 1963. And by the 1970s a division of labour had emerged: Israeli and Jewish historians wrote about the victims; the Germans inquired obsessively into the structure and functions of the Nazi state; while the Americans took a broader approach.

In 1970, the American historian Karl A Schleunes published The Twisted Road to Auschwitz, a pioneering work that challenged the idea that there was a direct route from Mein Kampf to the Final Solution. Schleunes argued that anti-Jewish policy was poorly developed when the Nazis came to power and jostled with other priorities. The regime, he insisted, had “stumbled” into genocide.

Through the 1970s and early 1980s research circled with increasing sterility around a narrow range of questions, drawing on the same limited range of sources. Had Hitler always intended to annihilate the Jews or did he drift into a murderous policy? Was there a single “Führer order” and if so, when was it issued? Was the genocide the result of planning or the consequence of “cumulative radicalisation”?

The principal figures in these exchanges were mostly West Germans: Eberhard Jäckel, a proponent of the “intentionalist” interpretation; Uwe Dietrich Adam, who followed Schleunes in arguing that the regime had lurched from one policy to another with no clear goal; and Martin Broszat, who exemplified the “functionalist” approach. It was an American, Christopher Browning, who blended the functionalist interpretation, in which human agency was downplayed, with a greater sensitivity to ideology and personality.

In 1982, the election of Helmut Kohl as West German chancellor opened the way to a controversial reassessment. Kohl wanted to “normalise” German history, treating the Nazi years as a phase in the longue durée of modernisation, and subsuming the Holocaust into a century of genocide. This agenda, and the efforts of Andreas Hillgruber and Ernst Nolte to tell a patriotic national story, triggered the “Historikerstreit”, a dispute about the singularity of Nazi crimes.

Kohl’s subsequent attempt to embrace the East Germans, following reunification, as victims of an undifferentiated totalitarianism that had lasted from 1933 to 1990 stimulated comparative studies. These in fact tended to underscore the specificity of Nazism. More significantly, the end of the Cold War allowed access to previously closed archives in the old Soviet bloc and enriched the corpus of available source material.

German reunification raised other unfinished business, such as the disposal of looted gold recovered from the Nazis in 1945. Swiss banks and German corporations, insurance firms, the art market and even railways were soon the subject of industrial-scale historical research by specially commissioned teams under the leadership of established scholars.

The resulting studies transformed the historical landscape. As Götz Aly concluded in Hitler’s Beneficiaries (2005), the transfer of wealth from Jews to Germans widened the circle of complicity to almost every German citizen. A similar dynamic extended across Europe and was summed up by Jan Gross in his recent book Golden Harvest. From France to Poland, non-Jews saw Jews as fair game, to be squeezed and then disposed of.

Meanwhile, explanations for the genocide were reshaped, first by postmodern theorists and then by the resurgence of national hatreds and ethnic cleansing unleashed by the collapse of communism.

In 1989, Zygmunt Bauman published Modernity and the Holocaust, in which he maintained that Nazi genocide was the apogee of Enlightenment rationality. Shortly afterwards, Michael Burleigh and Wolfgang Wipperman’s The Racial State sought to show how racial-biological thinking informed all official policy and infused everyday life in the Third Reich. The role of doctors, psychiatrists and demographers in applying eugenic ideas seemed to corroborate Bauman’s dark version of modernity.

Yet it was hard to think in such terms when the news was delivering images of slaughter from Bosnia and Rwanda. In Ordinary Men (1992), his study of a reserve police battalion that murdered tens of thousands of Jews in Poland, Browning had tilted in favour of situational factors such as peer pressure to explain the killers. By contrast, Daniel Goldhagen, whose book Hitler’s Willing Executioners (1996) examined the same cadre, concluded that they were driven by crude Judaeophobia. In his version the killers revelled in tormenting Jews before killing them in ways far removed from the industrial mass murder conjured up by Bauman.

By the end of the 1990s, personal agency and beliefs had become central to explaining both “perpetrators” and “bystanders”. To some extent, this reflected a shift from German to American scholarship. Robert Gellatelly, Eric Johnson and Peter Fritzsche argued that the Third Reich had relied less on coercion and more on consent. The Nazi concept of an idealised people’s community, was no longer dismissed as propaganda.

A new generation of young German historians produced a number of studies that amended our understanding of the timing and character of the Final Solution. While Hitler’s role remained decisive, it became apparent that his minions and satraps had far more autonomy than was once thought.

Jewish historians had long bemoaned the absence of a Jewish dimension from such research and the availability of vast collections of testimony, notably the USC Shoah Foundation, rendered the omission ever more untenable. But how to use it? Saul Friedländer’s magnificent volumes on Nazi Germany and the Jews (1997 and 2007), finally offered a model of how to write an “integrated” history that combined the conduct of the perpetrators with Jewish responses.

Fifty years after Arendt and Hilberg ruffled feathers, the “lessons of the Holocaust” seem no clearer and efforts to comprehend the Jewish tragedy continue to provoke as much controversy as reflection.

David Cesarani is research professor in history at Royal Holloway, University of London