In 1164AD, Salah ud Din Ayubi officially became a state employee of the Ismaili Fatimid Empire. He rose up the ranks owing to his charisma and military successes against Crusaders. Salah ud, as a Sunni Muslim began to undermine Fatimid regime by feigning loyalty. He managed to get the rank of a Vizer. After the death of Al-Adid in 1171AD, Salah ud Din Ayubi abolished the Cairo based Fatimid state and established Ayubbid Sultanate with himself as the First Sultan.

This shows that Salah ud Din Ayubi was indeed a man who possessed cunningness and also employed deception to achieve his goal of realigning Egypt with the Sunni based Abbasid Caliphate. The force behind Sultan Salah ud Din Ayubi Hazretleri was Sayyidina Abdul Qadir Jillani (رحمه الله تعالی) the leader of all Awliyah, Imam of all Orthodox Sunnis, and the 13th direct descendant of the Fifth Rightly Guided Caliph Sayyidina Imam Hassan ibn Ali رضي الله عنهم.

Source: "Saladin" Longman