It came as something of a surprise that a shortish book demands almost as much work as a longer one, and is just as much of a team effort. Thomas Penn at Penguin has been a scrupulously attentive and positive editor. Tom, Anna Hervé, Linden Lawson and Chloe Currens have made it a pleasure to write this book. My agent, Peter Straus, brought the Penguin Monarchs series to my attention before the books had started to come out, and encouraged me to take on the Cromwellian exception. Professor Ronald Hutton of Bristol University, who includes Cromwell and the Civil Wars among his many areas of expertise, was kind enough to read my text, and save me from the worst of my misapprehensions. At my work, two editors, Peter Stothard and Stig Abell, have cheerfully allowed me time to moonlight. At home, as always, Jules has unfailingly made space in a busier life to give me time to write, while my sons, Jude and Johan, have put up with another intruder from the distant past. As Oliver would have put it, ‘I am in good earnest thankful’.