Siege of Masyaf

The Siege of Masyaf was an engagement between the Saracen armies of Saladin and the Assassin Order, under the command of Al Mualim.

Following two failed attempts on Saladin's life, the Saracen warlord was unwilling to allow another, and so brought together a force of 10,000 Saracen warriors to descend upon the fortress of Masyaf. Ignoring the other nine Assassin strongholds, the Saracens made their way through the village and up the gates of the fortress. The next day the siege begun.

The following night, Al Mualim ordered the Master Assassin, Umar Ibn-La'Ahad to infiltrate the Saracen camp and provide a warning to Saladin, utilizing information gathered by an Assassin spy already in the camp. Umar was successful, leaving a feather and dagger in the warlord's tent, though he was forced to kill a nobleman during his escape.

The following day, Saladin left, although his son and second-in-command, Shihab Al'din, remained to negotiate the terms of peace. Shihab informed the Assassin that they would leave once they had the head of the nobleman's killer, Umar; his name had been learned from the captured spy, Ahmad Sofian. Although Al Mualim was reluctant to allow Umar to take Ahmad's place on the executioners' block, Umar's insistence and the threat of a prolonged siege, he eventually relented. Following Umar's execution, the Saracens left Masyaf.

Source

 * Assassin's Creed: The Secret Crusade