strategic place from which to control a country that was centered on the Nile river, much as the Ancient Egyptian city of Memphis (located just south of Cairo today) had done. (The pattern of founding new garrison cities inland was also one that was repeated throughout the Arab conquests, with other examples such as Qayrawan in Tunisia or Kufa in Iraq.) The foundation of Fustat was also accompanied by the foundation of Egypt's (and Africa's) first mosque, the Mosque of 'Amr ibn al-'As, which has been much rebuilt over the centuries but still exists today. Fustat quickly grew to become Egypt's main city, port, and economic center, with Alexandria becoming more of a provincial city. In 661 the Islamic world came under the control of the Ummayyads, based in their capital at Damascus, until their overthrow by the Abbasids in 750. The last Ummayyad caliph, Marwan II, made his last stand in Egypt but was killed on August 1, 750. Thereafter Egypt, and Fustat, passed under Abbasid control. The Abbasids marked their new rule in Egypt by founding a new administrative capital called al-'Askar, slightly northeast of Fustat, under the initiative of their governor Abu 'Aun. The city was completed with the foundation of a grand mosque (called Jami' al-'Askar) in 786, and included a palace for the governor's residence, known as the Dar al-'Imara. Nothing of this city remains today, but the foundation of new administrative capitals just outside the main city became a recurring pattern in the history of the area. Ahmad Ibn Tulun was a Turkish military commander who had served the Abbasid caliphs in Samarra during a long crisis of Abbasid power. He became governor of Egypt in 868 but quickly became its de facto independent ruler, while still acknowledging the Abbasid caliph's symbolic authority. He grew so influential that the caliph later allowed him to also take control of Syria in 878. During this period of Tulunid rule (under Ibn Tulun and his sons), Egypt became an independent state for the first time since Roman rule was established in 30 BC. Ibn Tulun founded his own new administrative capital in 870, called al-Qata'i, just northwest of al-Askar. It included a new grand palace (still called Dar al-'Imara), a hippodrome or military parade ground, amenities such as a hospital (bimaristan), and a great mosque which survives to this day, known as the Mosque of Ibn Tulun,