International audienceThe last quarter of the twelfth century marked the main turning point in the evolution of the Crusades and of Islamic military architecture: the rise of the Ayyubids in 1170, led by the malik Ṣalāḥ al-Dīn, led to the unification of Syria and Egypt under a single banner for the first time since the end of the tenth century, the renewal of the counter-crusades against the Franks and the fall of numerous Crusader castles in the Latin States, especially on the coasts of Syria shared by the County of Tripoli and the Principality of Antioch. On the other side of the borders, during the second half of the twelfth century, the Military Orders, mainly the Templars and the Hospitallers, played an increasing part in the Latin Sta...