NICHOLAS VINCENT is Professor of Medieval History at the University of East Anglia and a Fellow of the British Academy Daniel Power is Professor of Medieval History at Swansea University. He is the author of a number of works concerning France and the British Isles in the Central Middle Ages, including The Norman Frontier in the Twelfth and Early Thirteenth Centuries (2004). He is a Fellow of the Society of Antiquaries (of London) and of the Royal Historical Society. MATTHEW STRICKLAND is Professor of Medieval History at the University of Glasgow. NICHOLAS VINCENT is Professor of Medieval History at the University of East Anglia and a Fellow of the British Academy