He begins by analysing the sources for our knowledge of the military history of the period, assessing their reliability: some chroniclers exaggerate, others are careful observers or have access to official records. There follows an examination of the constituent parts of the medieval army, knights and footsoldiers, equipment and terms of service, behaviour on the field, and psychology, before the problematic question of medieval tactics is addressed through analysis of accounts of a series of major battles. Strategy is discussed in the context of these battles: whether to seek battle, fight a defensive war, or attempt a war of conquest.

This history of medieval warfare, originally written in 1885 when its author—later one of the great medievalists—was still an undergraduate at Oxford, remains for students and general readers one of the best accounts of military art in the Middle Ages between Adrianople in 378 A.D. (the most fearful defeat suffered by a Roman army since Cannae in 216 B.C.) and Marignano (1515 A.D.), the last of the triumphs of the medieval horseman. It was extensively revised and edited by John H. Beeler in 1953 to incorporate many new facts uncovered since the late nineteenth century.

The Art of War has been very simply defined as 'the art which enables any commander to worst the forces opposed to him.' It is therefore conversant with an enormous variety of subjects: Strategy and Tactics are but two of the more important of its branches. Besides dealing with discipline, organization, and armament, it is bound to investigate every means which can be adapted to increase the physical or moral efficiency of an army. Contents: The Transition from Roman to Mediæval Forms in War - A.D. 378–582. The Early Middle Ages - A.D. 476–1066–81. The Byzantines and their Enemies - A.D. 582–1071. The Supremacy of Feudal Cavalry - A.D. 1066–1346. The Swiss - A.D. 1315–1515. The English and their Enemies - A.D. 1272–1485.

George R.R. Martin's A Song of Ice and Fire novels and HBO's Game of Thrones series depict a medieval world at war. But how accurate are they? The author, an historian and medieval martial arts expert, examines in detail how authentically Martin's fictional world reflects the arms and armor, fighting techniques and siege warfare of the Middle Ages. Along the way, he explores the concept of "medievalism"--modern pop culture's idea of the Middle Ages.