sentences:  His release was eventually negotiated in return for a ransom (some of which was a loan from the Templars) and the surrender of the city of Damietta.A few years later, in 1253 he sought allies among both the Ismaili Assassins and the Mongols.When he saw a letter from Hethum's brother, the Armenian noble Sempad, which spoke well of the Mongols, Louis dispatched the Franciscan William of Rubruck to the Mongol court.