Thus William of Tyre explained the readiness of both Baldwin II (1118–32) and his enemy, Bursuqi of Mosul, to engage in battle at Azaz in 1125. But this may be taken as a text underlying the basic assumption of many writers, that crusading warfare was à l'outrance, unregulated mayhem. The twelfth century is certainly too early to speak of the ‘Laws of War’, because even within Catholic Christendom these only became codified and systematised from the thirteenth century onwards. But even at that date, certainly between warring contenders of the same religion, conventions had been established which ameliorated the brutality of war, especially regarding the treatment of prisoners, ransoms etc. The Anglo-Norman realm was in a state of continual conflict with some of its neighbours, but the behaviour of soldiers in these wars was governed by understandings which, though unwritten and uncodified, were nonetheless very influential. In Islam the redeeming of captives was a religious imperative and this formed the basis for a rather similar pattern of behaviour. Further, even before the crusades there were precedents for regulating the conduct of war between enemies of different religions.