David Crouch is Professor of Medieval History at the University of Hull. He is the author of several books, including The Reign of King Stephen (2002), The Birth of Nobility: Constructing Aristocracy in England and France, 1000–1300 (2005), The Normans (2005), The English Aristocracy, 1070–1272: A Social Transformation (2011), Lost Letters of Medieval Life: English Society, 1200–1250 (with Martha Carlin, 2013), The Acts and Letters of the Marshal Family, 1156–1248 (2015) and William Marshal (3rd edition, 2016).