|This article is about the highest rank of the Knights Hospitalier. You may be looking for other uses of the title.|
The Grand Master of the Knights Hospitalier is the supreme head of the Sovereign Military Hospitaller Order of Saint John of Jerusalem of Rhodes and of Malta, known in medieval times as the Knights Hospitalier.
In 1191, the Frenchman Garnier de Naplouse served as the Grand Master of the Hospitaliers. In secret, he was also one of the nine leaders of the Knights Templar subordinate to the Templar Grand Master Robert de Sablé. Naplouse held a nefarious reputation for his multiple scandals of human experimentation that led to his exile from France and Tyre. He was assassinated in 1191 by the Assassin Altaïr Ibn-La'Ahad on the orders of the Levantine Brotherhood leader Al Mualim in the midst of performing his experiments on patients—actually slaves provided by the Templar Talal—at the Hospitalier Fortress of Acre.
During the early 16th century, the Grand Master of the Knights Hospitalier aided his traditional Templar allies by having his forces capture several Assassins and holding them at his palace on Rhodes.