Sultan Al-Mu'izz, also known as Al-Mu'izz li-Din Allah, was the fourth ruler of the Fatimid Caliphate, reigning from 953 to 975 CE. He is notable for establishing Cairo as the capital of the Fatimid Empire in 969 CE, which became a significant center of culture and learning in the Islamic world. Under Al-Mu'izz's rule, the Fatimid Caliphate expanded its territory and influence, promoting trade and the arts. He was a patron of architecture, commissioning many important buildings, including the Al-Azhar Mosque, which remains a key institution in Islamic education today.