Sir Martin Gilbert is Winston Churchill's official biographer, and a leading historian of the modern world.  His book The Holocaust: The Jewish Tragedy (published in the United States as The Holocaust: A History of the Jews of Europe During the Second World War) is a classic work on the subject.  He is the author of seventy-two other books, among them the single-volume Churchill: A Life, his twin histories First World War and Second World War, a comprehensive History of Israel, and his three-volume work A History of the Twentieth Century (also published in a single, condensed volume). He is an Honorary Fellow of Merton College, Oxford, and a Distinguished Fellow of Hillsdale College, Michigan.