Author of Spies of the Balkans suggests:
I went out on book tour the second half of June, so for airplanes and hotel rooms I took along Ben Macintyre's Operation Mincemeat, about the British deception operation — a body floated to Spain — before the invasion of Sicily. When I'm back home, I'll indulge my taste for long, scholarly histories of periods I don't know much about with John Julius Norwich's Byzantium, three thick volumes for long summer days. I'm a believer in that classic definition of history as "one damn thing after another," and Norwich brings that approach to life. He's anecdotal and funny and understands that history doesn't play fair: it's all irrational outcomes, dumb luck, huge misunderstandings, humans at their best and worst.