An edition of Hugh Trevor-Roper’s wartime diaries, edited by Richard Davenport-Hines, was published in 2011. As few reviewers could resist mentioning, Trevor-Roper will always be more famous for (wrongly) authenticating Hitler’s diaries, than for his own.
In terms of interest in their diaries, literary figures generally do rather better. Virginia Woolf’s diary was published, in five magnificent volumes, in the early seventies, edited by Anne Olivier Bell, in what Lyndall Gordon says “may come to be seen as the editing feat of the century” (ODNB). Woolf knew so many people that her diaries are a rich source for many public figures of her time. For example, she describes a walk she took in 1918 with Lytton Strachey, in advance of the publication of a book of his, which she had refused to review because they were friends:
“I suspect that he is now inclined to question whether Eminent Historians, 4 in number, & requiring 4 years for their production, are quite enough to show for his age & pretensions. At anyrate he was evidently & rather painfully anxious about our opinion of their merits & came back so often though so tactfully to the question of my review that I hesitate.”
Eminent Victorians, of course, became a huge success without a puff from Virginia Woolf.
We can look for references to historians’ diaries in the Oxford Dictionary of National Biography: an advanced search for ‘historian’ in the statement of occupation and ‘diary’ or ‘diaries’ in full text gives 86 entries. But we find that, as with Trevor-Roper, many of the references are to the diaries of others which the historian edited or used as source material. Examples here include Colin Matthew’s lauded work on Gladstone’s diaries or John Hale’s use of diaries to investigate the history of popular ideas in the Renaissance.
But there are genuine examples of the historian’s diary illuminating the development of their thought:
“Tawney kept an occasional diary, published posthumously as his Commonplace Book, which illuminates the development of his social thought in this formative period. Alongside details of his students’ wages, piece-rates, and household budgets, Tawney focused on two issues: the nature of social equality and the means by which to achieve a socialist transformation.” [ODNB, by Lawrence Goldman]
Less instructive, but more amusing, is to discover the importance that AL Rowse attached to his own diary:
“Rowse insisted that his many publications represented only ‘the tip of the iceberg’ of his writing. He was alluding primarily to the diary that he kept for most of his adult life. At breakfast in All Souls he would often tell colleagues, especially any who had displeased him, that they had been included in the entry written the night before: ‘You’re in it and you’re in it’ (personal knowledge). He made clear that his diaries contained views even more trenchant than those in his published works. He incorporated material from the diaries into his various volumes of autobiography but much remained unused. He believed that when his diaries were published he would be ranked alongside Pepys; in any event, he contended, the project would make the Yale editions of Johnson and Boswell look like a minor cottage industry. The diaries remained unpublished at his death, and those colleagues who read them agreed that full publication would require both courage and good legal advice.” [ODNB, by John Clarke]