Islamic Cairo, also referred to as Medieval Cairo or Fatimid Cairo, was founded in 969 as the royal enclosure for the Fatimid caliphs, while the actual economic and administrative capital was in nearby Fustat. Fustat was established by Arab military commander 'Amr ibn al-'As following the conquest of Egypt in 641, and took over as the capital which previously was located in Alexandria. Al-Askar, located in what is now Old Cairo, was the capital of Egypt from 750 to 868. Ahmad ibn Tulun established Al-Qatta'i as the new capital of Egypt, and remained the capital until 905, when the Fustat once again became the capital. After Fustat was destroyed in 1168/1169 to prevent its capture by the Crusaders, the administrative capital of Egypt moved to Cairo, where it has remained ever since. It took four years for the General Jawhar Al Sikilli (the Sicilian) to build Cairo and for the Fatimid Calif Al Muizz to leave his old Mahdia in Tunisia and settle in the new Capital of Fatimids in Egypt.
After Memphis, Heliopolis, Giza and the Byzantine fortress of Babylon-in-Egypt, Fustat was a new city built as a military garrison for Arab troops. It was the closest central location to Arabia that was accessible to the Nile. Fustat became a regional center of Islam during the Umayyad period. It was where the Umayyad ruler, Marwan II, made his last stand against the Abbasids.
Cairo (pron.: // KYE-roh ); Arabic: القاهرة; is the capital of Egypt and the largest city in the Arab world and Africa. Its metropolitan area is the 16th largest in the world. Located near the Nile Delta, it was founded in 969 AD. Nicknamed "the city of a thousand minarets" for its preponderance of Islamic architecture, Cairo has long been a centre of the region's political and cultural life. Cairo was founded by the Fatimid dynasty in the 10th century AD, but the land composing the present-day city was the site of national capitals whose remnants remain visible in parts of Old Cairo. Cairo is also associated with Ancient Egypt as it is close to the ancient cities of Memphis, Giza and Fustat which are near the Great Sphinx and the pyramids of Giza.