‘Stratagem slipped into disuse in Europe during the Middle Ages […] As late as the Battle of Ravenna (1512) adversaries were accustomed to open battle, with chivalrous challenges and to conduct war, at least in theory, in accord with agreed rules and fixed means’. At least, this was the view of the twentieth-century military theorist Barton Whaley. The medieval chroniclers studied in this volume would have been astonished. They clearly thought that stratagems were an integral part of warfare: they depicted kings and emperors, crusaders and Muslims, nobles and commoners employing deception to achieve their goals.

Did all these incidents take place exactly as described? Almost certainly not. Many of them are probably fiction, fabricated by boastful warriors or by writers seeking to embellish their narratives. Their true value lies in what they tell us about medieval culture. The chroniclers evidently thought these stories were worth recording and that their readers would be interested in reading them. They are colourful, dramatic, often comical, contradicting any ideas about chronicles being ‘dry and dusty’. These incidents also tell us what qualities contemporaries admired in their fighting men, what kind of behaviour they thought was worthy of praise or censure. This is surely more useful to scholarship than whether Robert Guiscard really did have a ‘fake corpse’ carried into Montecassino or whether Louis the Fat actually infiltrated Gasny dressed in a monk's habit.

This study of the language and presentation of military deception has revealed a profound ambiguity towards the subject of trickery, not dissimilar to that found in our own culture. Different chroniclers could describe the same essential act as a nefarious fraud or a sound tactical decision. Deceitful behaviour could be ascribed to either treachery or prudence. The quality of ‘cunning’ could be attributed to both heroes and villains. Even the language used inhabited a grey zone of moral meaning, as the same phrases were also used for works of skill, engineering and rhetoric. Consider the subtle difference between ‘craft’, ‘craftsman’ and ‘crafty’ in modern English, or the range of meaning that be attached to words such as ‘artifice’ or ‘subtle’.