The fourth volume of The New Cambridge Medieval History covers the eleventh and twelfth centuries, which comprised the most dynamic period in the European Middle Ages. The first of two parts, this volume deals with ecclesiastical and secular themes, in addition to major developments such as the expansion of population, agriculture, trade, and towns; the radical reform of the Western Church; the appearance of new kingdoms and states, the Crusades, knighthood and law; and the development of literature, art and architecture, heresies and the scholastic movement. "This work, along with the others in this set, represent the finest in medieval scholarship at this point in time." --American Reference Books Annual The first 'religious and cultural' part of the fourth volume of The New Cambridge Medieval History. David Luscombe is Research Professor of Medieval History, University of Sheffield. Jonathan Riley-Smith is Dixie Professor of Ecclesiastical History, University of Cambridge, and Fellow of Emmanuel College.