[4] Trevor-Roper "enjoyed (but not too seriously) ... that he was a collateral descendant of William Roper, the son-in-law and biographer of Sir Thomas More ... as a boy he was aware that only a dozen lives (several of them those of elderly bachelors) separated him from inheriting the Teynham peerage.

Trevor-Roper was educated at Belhaven Hill School, Charterhouse, and Christ Church, Oxford, where he read first Classics (Literae Humaniores) and then Modern History.

[17] Using the alias of "Major Oughton", Trevor-Roper interviewed or prepared questions for several officials, high and low, who had been present in the Führerbunker with Hitler, and who had been able to escape to the West, including Bernd Freytag von Loringhoven.

[22] In June 1950, Trevor-Roper attended a conference in Berlin of anti-Communist intellectuals along with Sidney Hook, Melvin J. Lasky, Ignazio Silone, Arthur Koestler, Raymond Aron and Franz Borkenau that resulted in the founding of the CIA front group Congress for Cultural Freedom and its magazine Encounter.

[24] For Trevor-Roper, the major themes of early modern Europe were its intellectual vitality, and the quarrels between Protestant and Catholic states, the latter being outpaced by the former, economically and constitutionally.

[25] In Trevor-Roper's view, the witch hunts of the 16th and 17th centuries can ultimately be traced back to the conflict between the religious values of the Reformation and the rationalistic approach of what became the Enlightenment.

[27][28] Trevor-Roper attacked the philosophies of history advanced by Arnold J. Toynbee and E. H. Carr, as well as his colleague A. J. P. Taylor's account of the origins of World War II.

[32]: 342–43 Trevor-Roper was a very firm "intentionalist" who treated Hitler as a serious, if slightly deranged thinker who, from 1924 until his death in 1945, was obsessed with "the conquest of Russia, the extermination of the Slavs, and the colonization of the English".

[32]: 346  Trevor-Roper maintained that Hitler, on the basis of a wide range of antisemitic literature, from the writings of Houston Stewart Chamberlain to The Protocols of the Learned Elders of Zion, had constructed a racist ideology that called for making Germany the world's greatest power and the extermination of perceived enemies such as the Jews and Slavs.

[32]: 346 Trevor-Roper wrote that the mind of Hitler was "a terrible phenomenon, imposing indeed in its granite harshness and yet infinitely squalid in its miscellaneous cumber, like some huge barbarian monolith; the expression of giant strength and savage genius; surrounded by a festering heap of refuse, old tins and vermin, ashes and eggshells and ordure, the intellectual detritus of centuries".

[32]: 352  Cesarani wrote "Thus, to Trevor-Roper the values of Oxford University stood at the opposite pole to those of Hitler's Reich, and one reason for the ghastly character of Nazism was that it did not share them".

[32]: 352–53  Cesarani concluded that "to maintain the illusion of virtuous British liberalism, Hitler had to be depicted as either a statesman like any other or a monster without equal, and those who did business with him as, respectively, pragmatists or dupes.

[35] Trevor-Roper's "general crisis" thesis provoked much discussion, and led experts in 17th century history such as Roland Mousnier, J. H. Elliott, Lawrence Stone, E. H. Kossmann, Eric Hobsbawm and J. H. Hexter to become advocates of the pros and cons of the theory.

At times the discussion became quite heated; the Italian Marxist historian Rosario Villari, speaking of the work of Trevor-Roper and Mousnier, claimed that: "The hypothesis of imbalance between bureaucratic expansion and the needs of the state is too vague to be plausible, and rests on inflated rhetoric, typical of a certain type of political conservative, rather than on effective analysis.

[37] Another Marxist critic of Trevor-Roper, the Soviet historian A. D. Lublinskaya, attacked the concept of a conflict between "Court" and "Country" as fiction, arguing there was no "general crisis".

In a 3500 word essay published in The Sunday Times he said that the commission employed a "smokescreen of often irrelevant material" and "accepted impermissible axioms, constructed invalid arguments, and failed to ask elementary and essential questions".

[43] He wrote the introduction to Mark Lane's book Rush to Judgment[44] and was thanked in the acknowledgements section for being "kind enough to read the manuscript and make suggestions".

Trevor-Roper regarded Décadence Mandchoue with considerable distaste calling the manuscript "pornographic" and "obscene" as Backhouse related in graphic detail sexual encounters he claimed to have had with the French poet Paul Verlaine, the Irish playwright Oscar Wilde, Wilde's lover Lord Alfred Douglas, the French poet Arthur Rimbaud, the Russian ballet dancer Vaslav Nijinsky, the British Prime Minister Lord Rosebery and the Empress Dowager Cixi of China whom the openly gay Backhouse had maintained had forced herself on him.

For the next two years, Trevor-Roper went on an odyssey that took him all over Britain, France, Switzerland, the United States, Canada and China as he sought to unravel the mystery of just who the elusive Backhouse was.

[52][53] In 1960, Trevor-Roper waged a successful campaign against the candidacy of Sir Oliver Franks who was backed by the heads of houses marshalled by Maurice Bowra, for the Chancellorship of the University of Oxford, helping the Prime Minister Harold Macmillan to be elected instead.

Following Voltaire's remarks on the fall of the Roman Empire at the hands of barbarian tribes, he asserted that Africa had no history prior to European exploration and colonisation.

[55][56] These comments, recapitulated in a later article which called Africa "unhistoric", spurred intense debate between historians, anthropologists, sociologists, in the emerging fields of postcolonial and cultural studies about the definition of "history".

[61] Many historians now argue, against Trevor-Roper, that historical evidence should also include oral traditions as well as any type of written history, a former criterion for a society having left "prehistory".

The British journalist Neal Ascherson summarised the quarrel between Cowling and Trevor-Roper as:Lord Dacre, far from being a romantic Tory ultra, turned out to be an anti-clerical Whig with a preference for free speech over superstition.

He did not find it normal that fellows should wear mourning on the anniversary of General Franco’s death, attend parties in SS uniform or insult black and Jewish guests at high table.

For the next seven years, Trevor-Roper battled to suppress the insurgency of the Cowling clique ("a strong mind trapped in its own glutinous frustrations"), and to bring the college back to a condition in which students might actually want to go there.

Some of the contributors were Sir Geoffrey Elton, John Clive, Arnaldo Momigliano, Frances Yates, Jeremy Catto, Robert S. Lopez, Michael Howard, David S. Katz, Dimitri Obolensky, J. H. Elliott, Richard Cobb, Walter Pagel, Hugh Lloyd-Jones, Valerie Pearl and Fernand Braudel.

[73] The topics contributed by this group of American, British, French, Russian, Italian, Israeli, Canadian and German historians extended from whether the Odyssey was a part of an oral tradition that was later written down, to the question of the responsibility for the Jameson Raid.

[74] On 4 October 1954, Trevor-Roper married Lady Alexandra Henrietta Louisa Howard-Johnston (9 March 1907 – 15 August 1997),[75] eldest daughter of Field Marshal The 1st Earl Haig by his wife, the former Hon.

In 2002, at the age of 88, Trevor-Roper submitted a sizable article on Thomas Sutton, the founder of Charterhouse School, to the Oxford Dictionary of National Biography in part with notes he had written decades earlier, which editor Brian Harrison praised as "the work of a master".