When Saladin captured Jerusalem in 1187, Pope Gregory VIII announced the Third Crusade and managed to enlist Richard of England, Philip II of France, and Fredrick Barbarossa of the Holy Roman Empire.
When Fredrick drowned on the journey, Richard and Philip couldn't get along. Richard managed to capture Acre, and secured Cyprus, which remained in European hands until the Turks took it in 1571. Crusader armies pushed as far as Jaffa, but after seeing the strength of the Jerusalem defenses, turned back without assaulting Jerusalem, their ultimate objective.
In The Templar Concordat, it is this crusade which prompts the Treaty of Tuscany.