Al-Kamil () (full name: al-Malik al-Kamil Naser ad-Din Abu al-Ma'ali Muhammad) (c. 1177 – 6 March 1238) was a Muslim ruler and the fourth Ayyubid sultan of Egypt. During his tenure as sultan, the Ayyubids defeated the Fifth Crusade. He was known to the Frankish crusaders as Meledin, a name by which he is still referred to in some older western sources. As a result of the Sixth Crusade, he ceded West Jerusalem to the Christians and is known to have met with Saint Francis. Biography Jazira campaign Al-Kamil was the son of sultan al-Adil ("Saphadin"), a brother of Saladin. Al-Kamil's father was laying siege to the city of Mardin (in modern-day Turkey) in 1199 when he was called away urgently to deal with a security threat in Damascus. Al-Adil left al-Kamil to command the forces around Mardin continuing the siege. Taking advantage of the Sultan's absence, the combined forces of Mosul, Sinjar and Jazirat ibn Umar appeared at Mardin when it was on the point of surrender, and drew Al-Kamil into battle. He was badly defeated and retreated to Mayyafariqin. However dissent and weakness among his opponents meant that Al-Kamil was able to secure Ayyubid rule in the Jazira Region by taking Harran (in modern-day Turkey). Viceroy of Egypt In 1200, after proclaiming himself Sultan, Al-Adil invited Al-Kamil to come from the Eastern Territories to join him in Egypt as his viceroy (na'ib) in that country. Al-Adil's second son, Al-Mu'azzam Isa, had already been made prince of Damascus in 1198. It appears that Al-Adil allowed Al-Kamil a fairly high degree of authority, since he oversaw much of the work on the Cairo Citadel, issued decrees in his own name, and even managed to persuade his father to dismiss the powerful minister Ibn Shukr. Al-Kamil remained viceroy until his father's death in 1218 when he became Sultan himself. The Fifth Crusade In 1218 when Al-Adil died, the Ayyubid domains were divided into three parts, with Al-Kamil ruling Egypt, his brother Al-Muazzam Isa ruling in Palestine and Transjordan, and a third brother, Al-Ashraf Musa in Syria and the Jazira. Nominally the other two recognised Al-Kamil's supremacy as Sultan. Unusually for an Ayyubid succession, there was no obvious dissent or rivalry between the brothers at this point, partly because just before Al-Adil's death, Egypt had been attacked by the forces of the Fifth Crusade. Al-Kamil took command of the forces which defended