The Third Crusade (1189 – 1192), also known as the Kings' Crusade, was an attempt by many of the leaders of medieval Christendom to reconquer the "Holy Land" of Jerusalem from Salāh ad-Dīn Yūsuf ibn Ayyūb, better known as "Saladin". During this crusade, Christian forces, principally led by King Richard I of England, managed to reclaim Acre and engaged Saladin at Arsuf before coming to negotiate peaceful terms.
Richard I of England, the leader of the Crusaders, began his campaign by conquering Cyprus and then triumphed at the siege of Acre, after which three thousand captives were slaughtered by his knights. The Crusaders mobilized their forces to march south to Jaffa, and then on to their ultimate goal, Jerusalem. Saladin gathered his troops before the broken citadel of Arsuf, determined to halt the Crusaders and keep Jerusalem in Muslim hands.
At the Battle of Arsuf, Richard led the Crusader army against Saladin's forces. During this time, Robert de Sablé, Grand Master of the Knights Templar, asked Richard to unite with Saladin against the Assassins, who were behind the murders of eight influential Crusaders and Saracens. Before de Sablé could complete his proposition, the Assassin Altaïr Ibn-La'Ahad arrived after fighting his way across the battlefield of Arsuf in search of the Templar Grand Master.
Altaïr told King Richard of de Sablé's ulterior motives, which de Sablé denied. King Richard decided that both men should fight, believing that the Lord would protect the one who spoke the truth. After a long battle, Altaïr defeated de Sablé, who then revealed that Altaïr's master, Al Mualim, was also a Templar. Following this, Altaïr left for Masyaf to confront his mentor, and King Richard bid the Assassin a safe journey.