collinsQ. How do you go about writing? Don’t you feel daunted by a book on the scale of The American Panorama or the complexity of St George and the Dragons?

A. I’m inspired by my great undergraduate teacher, J. M. (John) Roberts, who wrote A History of the World, A History of Europe and The Triumph of the West. He told me he wrote some passages in the morning, then turned to something else, then came back and reviewed what he’d written. I divide my tasks into manageable chunks and subdivide them if need be. I may work on several chapters at the same time if relevant thoughts and materials come to hand. When a chapter seems complete it’s important for me to make sure it has a unifying theme summarized in an introductory paragraph. Roberts’ History of Europe has a summary page printed before each chapter.

Q. How quickly do you write? Do you obsess over things?

A. Like another of my great undergraduate teachers, J. R. L. Highfield (Spain in the Fifteenth Century 1369-1516, A History of Merton College, Oxford) I’m a perfectionist. I’ve re-written and reorganized chunks of my books and am constantly looking to correct inaccuracies, repair omissions and express myself more clearly and forcefully. Although I’ve written so much, I regard myself as an amateur at the craft of writing and am always learning from others and trying new approaches.

Q So what do you actually do when you sit down to write?

A. There are basically two methods of compiling a long and complex text. The author can lay the structure out like an engineering drawing, or plot it like a chess strategy (Alexandre Dumas of Les Misérables fame worked like that). Or he can start writing and see what happens, like Dickens, which is more like what I do. Dickens had a china monkey with a face like a man in front of him on his desk and said he used it to help start a train of imagination. This unplanned method might seem risky, especially for someone like Dickens, who generally had to publish in serial form, weekly or monthly. But Dickens, one of the most successful writers ever, was only short of material twice in 20 years. (You can still see the monkey, by the way, at the Dickens House Museum, 58 Doughty Street, London. )

I write longer texts like Elgar wrote his symphonies and concertos, in pieces, even individual paragraphs. These I may scribble down on odd word processor pages or paper sheets I call my ‘scribbles and scraps’. Then I work them up into one or more paragraphs, sometimes revising once or twice, other times more often over days.

I like favourite pieces of classical music, so handily downloadable on YouTube, to get me in the mood and motivated. But as soon as I feel the urge to write I click the music off. I must have silence when I write: no telephone, mobile phone, or interruptions of any kind.

Q. What advice would you give to anyone starting out to write a nonfiction book?

A. Well, I wouldn’t presume to give an experienced writer advice, although I’d probably enjoy discussing the challenges of writing with him or her. But my advice to students is to quote the dictum of Eisenhower: ‘Plans are useless; planning is everything’. He meant, I think, not to obsess about methodology but focus on objectives. As he got to be Supreme Allied Commander, I think he knew something. If you write by choice, you have to write about something that absorbs, enthuses, inspires you. After all, it isn’t words that inspire a writer but her theme.

Q. But how do you keep control of the structure?

A. Advice I often repeat to students is some I received from one of my postgraduate supervisors, G. V. Bennett (The Tory Crisis in Church and State: The Career of Francis Atterbury). He used to insist that before I wrote a chapter on my research I stated in one sentence what it was going to be about; we might spend most of the supervision hour crafting that sentence to clarify my focus and hence select from a mass of notes the material I was going to present.

Q. You mentioned two great authors. Are there any others you admire?

A. An author I admire for his methods is Trollope (see Richard Mullen’s biography Anthony Trollope: A Victorian in His World ). As a young man, when I was even greener in judgement than I am now, I used to despise Trollope as a superficial author best taken on a seaside holiday. Now I admire him as perhaps not among the greats but well up in the second rank. Trollope was in charge of the British Post Office for years but he made time before work each day to pen 300 words. He followed an essential discipline for a writer: to get your draft. You have to write it down, however bad it may seem. Revising comes later; less revising comes with lots of practice.

Q. Can people send you their drafts for advice?

A. Yes, by all means. I’ll be happy to help anyone if I can.