The Sixth Crusade
Seven years after the failure of the fifth crusade, Holy Roman Emperor Frederick II began what is known as the sixth crusade, following his excommunication by Pope Gregory IX for his repeated failure to embark on a crusade. In 1225 Frederick had married Yolande, or Isabella, of Jerusalem, the daughter of the nominal King of Jerusalem, John of Brienne, giving him a claim to the broken up Kingdom of Jerusalem.
Following his excommunication, Frederick sailed to Cyprus on his way to Acre, then capital of the Kingdom of Jerusalem. After a breakdown of talks with the Ibelin faction in Cyprus, and split support among the crusaders, including the Templars and Hospitallers, Frederick sought discussions with the Sultan of Egypt to seal the peaceful surrender of Jerusalem. Fearing Frederick’s strong force along the coast, the Sultan ceded Jerusalem and various coastal areas to the Franks, but on condition, the Dome of the Rock remained with the Moslems. Frederick also gained control of Nazareth, Jaffa, Sidon and Bethlehem.