“I am writing all the time. I am writing when I am flying in a plane. I don’t mean literally writing; I am thinking about it. People often say to me, ‘How much of your time do you spend writing and how much of your time do you spend doing research?’ It is a great question, but no one ever says, ‘How much of your time do you spend thinking?’ That is probably the most important part of it — just thinking about it, thinking about what you have read, what you need to read, what you need to think more about. Putting things out literally on the table and looking at them. Putting a reproduction of a painting and really looking at that painting and thinking about that painting or the setting. Where things happened is very important to me. This whole book that I have just written [“The Greater Journey”] is set in Paris. Another book I wrote [“The Great Bridge”] was set in Brooklyn. Another was set in Panama [“The Path Between the Seas”]. Much of several books have been set here in Washington. I believe that the setting has great effect on the way things happened, the way things went. The setting is part of history, just as the ‘who’ is part of the why and so I really have to soak up the setting.
Historian David McCullough, explaining his writing process on CSPAN’s Q&A, May 2011 (via deadpresidents)