A regular officer with the 11th Hussars, he left the Army to write.
He has published four novels, and numerous works of non-fiction. His books include The Spanish Civil War; Inside the British Army; Crete -- The Battle and the Resistance, which was awarded a Runciman Prize, and Paris After the Liberation, 1944-1949 (which was written with his wife Artemis Cooper).
Stalingrad, first published in 1998, won the first Samuel Johnson Prize, the Wolfson Prize for History and the Hawthornden Prize for Literature in 1999. Berlin - The Downfall 1945, published in 2002, was accompanied by a BBC Timewatch programme on his research into the subject. D-Day - The Battle for Normandy, published in June 2009, has been a No 1 Bestseller in seven countries, including the UK and France, and in the top ten in another eight countries.
His last book, The Second World War, published in June 2012, was translated into twenty-one languages. His latest book is Ardennes 1944: Hitler’s Last Gamble.