This is the first detailed study of the behavior in war of the military aristocracy in England and Normandy from the Norman Conquest to the reign of King John (1066-1217). Though methods of warfare are integral to the book, the emphasis is on conduct in battle and siege rather than with tactics and strategy. It explores ideas of ransom and the treatment of prisoners, the extent to which there was a "brotherhood in arms" among noble opponents, and how the knights treated the peasantry and churchmen in wartime.