During my research I used a number of excellent histories and first-hand accounts. For those readers who would like to delve further, I recommend the following:
Giles St Aubyn, The Royal George, 1819-1904: The Life of H.R.H. Prince George Duke of Cambridge (1965)
J. Duke, Recollections of the Kabul Campaign 1879 & 1880 (1883)
T.A. Heathcote, The Afghan Wars: 1839-1919 (2007)
David Loyn, Butcher & Bolt: Two Hundred Years of Foreign Engagement in Afghanistan (2008)
Field Marshal Lord Roberts of Kandahar, Forty-One Years in India: From Subaltern to Commander-in-Chief (1898)
Brian Robson, The Road to Kabul: The 2nd Afghan War 1878-1881 (2008)
William Trousdale (ed.), War in Afghanistan, 1879-80: The Personal Diary of Major General Sir Charles Metcalfe MacGregor (1985)
Switching from history to fiction is never easy. Fortunately I've been guided by an excellent editorial team at Hodder - notably my publisher Nick Sayers and his (former) assistant and now editor Anne Clarke - and once again they've come up trumps. I have Nick to thank for suggesting I consult the screenwriter Guy Meredith while I was plotting this book (in an attempt, no doubt, to iron out the wrinkles of its predecessor) and Guy's input has been invaluable. And to everyone else at Hodder who has worked so hard on the book - Laura, Kerry, Claudette, Helen, Mark, as well as Auriol, Lucy, Jason and their teams, in particular Aslan - not to mention my excellent freelance copy-editor Hazel Orme, proof-reader Barbara Westmore, and Martin Collins who drew the maps, I'm extremely grateful.
Thanks, also, to Richard Foreman and Peter Robinson, my publicist and agent respectively, who between them made this transition to fiction possible; and, last but not least, to my wife Louise for reading the manuscript (and enjoying it for a change), and making the extremely sensible suggestion that I should leave the writing of sex scenes to those 'who know what they're doing'.