Hilberg was a refugee from Austria; his family had escaped the Nazi dragnet just in time in 1939. Now he was handling books that belonged to the man bent on eradicating all European Jews.
On his return to New York, Hilberg dedicated his life to unearthing evidence of arguably the worst single crime in modern history. Jettisoning his chemistry studies, he took up political science at Brooklyn College, and later, at Columbia University. He insisted on writing his doctoral dissertation on the Holocaust, although he was advised that the idea could damage his academic career; there was still a reluctance in America to acknowledge the full horror of the catastrophe. But Hilberg was adamant. As he wrote in his 1996 memoir, The Politics of Memory: Journey of a Holocaust Historian: "[My supervisor] Franz Neumann realised that I was separating myself from the academic mainstream to tread in territory that had been avoided by the public and academia alike."
The resultant 1955 thesis became The Destruction of the European Jews, though it was not until a small publishing house in Chicago accepted it six years later that the work appeared. Expanded from 700 to 1,273 pages, and widely translated and updated, it remains "the single most influential work in our field and the benchmark for the discipline," according to Paul Shapiro, director of the Centre for Advanced Holocaust Studies at the US Holocaust Memorial Museum in Washington DC.
In 1945, one inscription from the Hitler crate particularly caught Hilberg's eye: a dedication to "the architect", referring to the führer's earlier would-be career. Sixty years later, Hilberg recalled the moment in a lecture at the Holocaust museum. "I saw that Hitler was really an architect of destruction. The process of destruction has an architectural form, and it would be an unfinished edifice if any Jews were left alive."
Hilberg's work stressed the systematic way in which a "far-flung, sophisticated bureaucracy" made mass murder commonplace. An inexorable process ensued: identifying "the Jew", removing him from the economy, then ghettoisation and finally annihilation. Formal orders gave way to a network of understood hints. Clerks, gas chamber architects, factory owners, accountants and train schedulers competed for opportunistic new "solutions". Thus everyone was complicit, yet no one accepted responsibility. Hannah Arendt embroidered that theme in Eichmann in Jerusalem: a Report on the Banality of Evil (1963), which relied heavily on Hilberg's research.
Hilberg, professor of political science at Vermont University from 1956 to 1991, was devoted to documentation-based fact. But he could still be moved to tears by small examples of cruelty or pathos - the story of a doomed Warsaw Jew protesting over a missing coffee coupon, or Hilberg's discovery of a slain man's chemistry books. At times, the truth could seem unpalatable, such as his conclusion - unpopular in Jewish circles - that resistance to the Nazis was the exception not the rule, and that some Jews collaborated with their tormentors in the hope of saving a few lives.
Hilberg believed that the Holocaust should not be seen in isolation, either from other wartime events or from other acts of genocide. Returning through the American deep south in the 1940s, he was shocked to see separate benches for blacks and whites. "Don't tell me that what happened [in Europe] can't happen some place else," he told a colleague. More recently, he repeatedly challenged gender and racial discrimination, chastised President Bill Clinton for dithering over the Rwandan genocide in 1994, and petitioned the US Congress to recognise the 1915-17 Turkish massacre of Armenians.
Hilberg was born in Vienna; he was 12 when the Nazis invaded Austria in 1938. The following year, his father got the family on to a ship to Cuba, en route to New York. Raul interrupted his chemistry studies to enlist with the 45th Infantry Division in Europe. Given his proficiency in German, he was soon poached by the US army documentation division.
Back in peacetime America, he took an MA at Columbia University's school of public law in 1950. The following year he began microfilming and scrutinising millions of Nazi documents in the Alexandria project, located in a disused torpedo factory in Virginia. For a while he taught, in Spanish, at a college in Puerto Rico. Then, in 1956, he moved to Burlington, Vermont, with his first wife, Christine.
Hilberg served on the president's commission on the Holocaust (1978-79) and the US Holocaust memorial council (1980-88). He helped unlock long- closeted Soviet archives, and inspired a generation of German scholars. In 2006, he was awarded the Order of Merit, Germany's highest honour for a non-citizen. His other books include Perpetrators, Victims, Bystanders: the Jewish Catastrophe 1933-1945 (1992) and Sources of Holocaust Research: an Analysis (2001).
He is survived by his second wife, Gwendolyn, whom he married in 1980, and David and Deborah, the children of his first marriage.
· Raul Hilberg, historian, born June 2 1926; died August 4 2007