ABSTRACT
This chapter suggests that the differences between the European sources and William's account are due partly to the different sources used by each, but also to their different purposes in writing. For the Hospitallers' dispute with the patriarch of Jerusalem and the invasion of Egypt, William of Tyre is the best source but in each case the European source provides a welcome second opinion and allows to amend his picture slightly. William of Tyre's history of the kingdom of Jerusalem has dominated authors’ research into the military orders in the Holy Land for the period between the end of the Second Crusade and William's own death. After William of Tyre's history became well known in Europe, from 1190 onwards, Europeans writing about the Holy Land in the twelfth century usually relied on William or one of the French adaptations of his work for their information.
