Hans-Ulrich Wehler, the most influential German historian of the post-second-world-war era, has died aged 82. The question of the long-term roots of nazism in German history was first opened up by Fritz Fischer, a historian of the previous generation, in the early 1960s, through a comparison of German war aims in 1914-18 and 1939-45. Wehler took this line of inquiry further by extending it to the formation, or in his view malformation, of German society in the 19th century, revolutionising the study of German history in the process.
He did this by applying American modernisation theory, which held that industrialisation would be accompanied by increased social mobility and political democracy, and a Marxist concept of class conflict. Using this approach, he argued forcefully that Germany's path to modernity deviated from the western norm with the failure of the 1848 revolutions, allowing the continued domination of an anti-democratic, anti-modern aristocratic elite while elsewhere the bourgeoisie seized control of events and drove on the modernisation of the rest of western Europe to its full conclusion.
The result in Germany was a modern industrial economy that failed to bring with it the normal accompaniments of social mobility and political democratisation. When these threatened finally to arrive, under the Weimar Republic, the elites, into which the aristocracy had incorporated a "feudalised" and deferential bourgeoisie, steadily undermined the institutions of the new political system until they were able to lever Hitler into power in 1933.
Wehler first put forward these views in his remarkable short work The German Empire 1871-1918, first published in German in 1973 and the only one of his books to be translated into English. It consisted of brief, argumentative sections, originating in lectures that his students in Cologne had begged him, as a young, leftwing teacher, to write, delivered to packed lecture theatres in an atmosphere of almost revivalist enthusiasm. Nothing like them had ever appeared in print in Germany, and the book had an enormous impact, its arguments discussed in seminars and dissected in dissertations and articles for many years afterwards.
Over the following decades, Wehler turned to writing a full-scale "societal history of Germany", the Deutsche Gesellschaftsgeschichte, in five enormous volumes, each some 1,000 pages long, covering the economic, social, cultural and political history of Germany from the early 18th century to the present. These have become a standard work of reference for generations of German students.
Inevitably, many of the clear theses articulated in the 1973 tract are toned down, blurred or modified or disappear under mountains of facts in the larger work. Wehler's relentlessly structural approach means that for hundreds of pages human beings barely put in an appearance. It is surprising, therefore, that he places so much weight on the individual personalities of Bismarck and Hitler, whose power he analyses in terms of Max Weber's concept of charisma; the absence of vivid character-sketches elsewhere in the books makes them stand out all the more.
Yet the detailed accounts of a staggering variety of topics are utterly engrossing. As an enthusiast for a particular concept of modernity as the triumph of reason, Wehler was dismissive of anything he regarded as an obstacle to progress, such as Catholicism, where at times he seemed to be refighting the Kulturkampf, the anti-Catholic "culture struggle" of the 1870s. The social-scientific and quantifying approach he took meant that he left out of the account whole swaths of the German past, including women, sexuality, popular culture, sickness and health, science, literature, culture and the arts, to concentrate on a history defined by class structure and political action.
Still, he seemed to have read everything published on virtually every topic he touched on in these volumes, and littered his bibliographical notes with waspish comments on works of which he disapproved – one book is described as "useless and unreliable in every respect", another "a collection of glaring false judgements", an article (inevitably, one of mine) is written off as "pretentious and inexact". Wehler could be a harsh and sometimes unfair reviewer of other people's work, but he was never dull.
Born in Freudenberg, Westphalia, the son of Theodor Wehler, a minor businessman, and his wife, Elisabeth (nee Siebel), he attended the primary and grammar schools in Gummersbach, a small town 50 kilometres east of Cologne. His parents were Protestants and he inherited a strong dose of the work-ethic that he later ascribed to this tradition.
Hans-Ulrich belonged to the "flak-helper" generation of young Germans who experienced the last days of the war as adolescents drafted in to man the air defences, such as they were. He was enrolled in the same unit of the Hitler Youth as Jürgen Habermas, later a philosopher to whom he remained intellectually close for the rest of his life.
After Germany's defeat, he studied history and sociology at the Universities of Cologne and Bonn, and took a Fulbright scholarship at Ohio University, where he acquired the midwestern twang with which he spoke English.
For six months he worked as a welder and a truck driver in Los Angeles, losing in the process any remaining academic formality; he signified his rejection of traditional professorial behaviour by always wearing white trainers and a turtleneck pullover with his suits. In Germany he completed a doctoral dissertation with the senior modern historian at Cologne, Theodor Schieder, for whom he retained a reverence that was only slightly dented by the revelation, years later, of Schieder's active participation in Nazi plans for the ethnic cleansing of eastern Europe during the war.
Wehler began researching for his obligatory second dissertation, on US imperialism, but in the cold war atmosphere of the 1960s this was ruled inadmissible by the university authorities, so he turned the same methods and concepts instead to a study of Bismarck and Germany's bid for colonies in the 1870s, developing the argument that empire and overseas conquest were primarily designed to overcome class conflicts and antagonisms at home, a proposition that generated fruitful debate and aroused widespread criticisms from a variety of perspectives. Once the work had been accepted and published, in 1969, he turned again to US imperialism, producing a book on the subject in 1974.
After short-term teaching positions in Cologne and Berlin, Wehler moved in 1971 to the new university of Bielefeld, where he remained for the rest of his career. Surrounded by like-minded historians, he created what became known as the "Bielefeld school", which spawned a vast series of pioneering PhD dissertations, reprints of neglected works by radical predecessors such as Eckart Kehr and Hans Rosenberg, conferences, research projects, essay collections and articles, many published in the journal he founded with his colleagues, Geschichte und Gesellschaft (History and Society).
To deliver a paper in his seminar was like entering a gladiatorial arena; a score or more of brilliant PhD students and junior faculty vied with each other to see who could destroy the visiting speaker most comprehensively. Yet none of this was done with ill-will; like their mentor, they loved argument and disputation, and to survive the intellectual cauldron of Bielefeld could be a heady experience for the outsider.
Wehler's combative and argumentative nature also expressed itself in a stream of polemical essays and reviews, which he published in a series of collected volumes, the most recent of which, The Germans and Capitalism, appeared this year. He inveighed in the press against growing social inequality in modern Germany, against the Turkish application to join the EU, against the attempt to whitewash the German past in the so-called Historians' Dispute of the 1980s, against racism and Holocaust denial, and much more besides. He believed strongly in the historian's duty to engage in public debate, and had become one of Germany's most provocative intellectuals, and a leading public figure.
Wehler was awarded numerous prizes and held visiting professorships at Harvard, Yale, Princeton and Stanford. He retired in 1996 but continued to live mainly in Bielefeld, from where he carried on his energetic and unceasing engagements with the great issues of the German past and present.
In 1958 he married Renate Pitsch. She survives him, as do their sons, Markus, Fabian and Dominik.
• Hans-Ulrich Wehler, historian, born 11 September 1931; died 5 July 2014
