The Age of Chivalry

The Age of Chivalry ... [is] an appropriate label for the years between roughly 1100 and 1500. Even the Age of Chivalry, however, began in Rome.... In Roman eyes, "every war needed justification. The best reason for going to war was defence of the frontiers, and almost as good, pacification of the barbarians living beyond the frontiers. Outside these reasons one risked an unjust war, and emperors had to be careful." But within these limits, the conduct of war was essentially unrestrained. Prisoners could be enslaved or massacred; plunder was general; and no distinction was recognized between combatants and noncombatants. Classical Latin, indeed, lacked even a word for a civilian. The merciless savagery of Roman war in this sense carried on into the invasion period of the fifth and sixth centuries.... This was a style of warfare that was appropriate only against a non-Roman enemy, and in the Middle Ages this came to mean that Christians ought only employ it against pagans, like the Muslims in the Holy Land or, in the sixteenth century, the aboriginal peoples of the New World.... [This philosophy celebrated] war by God's people for God's own purposes.... [S]o long as it was fought for pious ends, such warfare knew no effective limits. The wars of conquest which Charlemagne waged against the pagan Saxons during the eighth century thus qualified perfectly as a Roman war. After thirty years of plunder, massacre, mass enslavement, and mass deportations the Saxons finally saw the reasonableness of Christianity and agreed to accept Baptism at the hands of the Franks....

Ecclesiastical efforts to restrain intra-Christian violence during the tenth and eleventh centuries did bear some fruit, however, and it is with them that we begin to see the modern outlines of the laws of war as these would emerge in the Age of Chivalry. Carolingian church councils issued a number of decrees which demanded that noble miscreants give up their belt of knighthood, their cingulum militaire, as part of the punishment for their crimes. We see in these measures our first evidence that the bearing of arms was seen as a noble dignity connected with a code of conduct, the violation of which might cost a man his status as a warrior....

[Changes in the society, politics, and the advent of the cavalry intensified warfare during the eleventh century.] With respect to the laws of war, two consequences followed from these developments. First, long-established but only dimly perceptible codes of noble conduct on the battlefield began to be applied to the knights as well. A greater number of fighters were now covered by these standards of honorable conduct. In 1066, for example, William the Conqueror expelled from his militia a knight who struck at the dead Harold's body on the battlefield with his sword....[K]nighthood had clearly emerged by 1100 as an indissoluble amalgam of military profession and social rank that prescribed specific standards of behavior to its adherents in peace and war. The laws of war would develop in the Age of Chivalry as a codification of these noble, knightly customs on the battlefield. Second, however, the sharp division which this knightly elite now drew between itself as an order of bellatores and the rest of society mad up on oratores or laboratores meant that laws of war themselves applied only to other nobles. In theory, peasants and townspeople ought not to fight at all.... If such common men did fight - and in practice they did, regularly - then no mercy was owed to them on the battlefield or off. In the ordinary circumstances of battle a knight ought not kill another knight if it was possible instead to capture him for ransom. Armed peasants and townsmen, however, could be massacred at will....

As an enforceable body of defined military custom, the laws of war as we are discussing them emerged [] out of the interplay of knightly custom with Roman law as this was studied and applied in court from the twelfth century on. By the fourteenth century this combination of knightly practice and legal theory had given rise to a formal system of military law, jus militaire, the law of the milites, the Latin word for knights. The enforceability of this law, at least in the context of the Hundred Years War, needs to be stressed. Charges brought under the laws of arms were assigned to special military or royal courts - the Court of Chivalry in England, the Parlement of Paris in France - where lawyers refined and clarified its precepts in formal pleadings. Knights and, of course, heralds, remained the experts in the laws of arms. Their testimony was sought both in defining the law and in applying it to specific cases, a reflection of the status of jus militaire as a body of international knightly custom. From the fourteenth century on several attempts were made to record these customs in writing, the most famous being Honoré Bouvet's Tree of Battles. Like all medieval lawbooks these were partial and tendentious with a bias toward kings. The real history of the laws of war in the Age of Chivalry is buried in the hundreds of court cases brought under it and in the scores of chroniclers accounts of the conduct of war ...

-Robert C. Stacey (from The Laws of War: Constraints on Warfare in the Western World)