In 1186, Bertrand Mazoir sold Margat to the Hospitallers as it was too expensive for the Mazoir family to maintain. After some rebuilding and expansion by the Hospitallers it became their headquarters in Syria. Under Hospitaller control, its fourteen towers were thought to be impregnable.

Many of the more substantial Christian fortifications in the Holy Land were built by the Templars and the Hospitallers. At the height of the Kingdom of Jerusalem, the Hospitallers held seven great forts and 140 other estates in the area. The property of the Order was divided into priories, subdivided into bailiwicks, which in turn were divided into commanderies.