Thomas Asbridge is Reader in Medieval History at Queen Mary, University of London, and the author of 'The Greatest Knight: The Remarkable Life of William Marshal, the Power Behind Five English Thrones' (2014), 'The Crusades: The War for the Holy Land' (2010) and 'The First Crusade: A New History' (2004). He studied for a BA in Ancient and Medieval History at Cardiff University, and then gained his PhD in Medieval History at Royal Holloway, University of London.