The city reached its peak in the 12th century, with a population of approximately 200,000. It was the center of administrative power in Egypt, until it was ordered burned in 1168 by its own vizier, Shawar, to keep its wealth out of the hands of the invading Crusaders. The remains of the city were eventually absorbed by nearby Cairo, which had been built to the north of Fustat in 969 when the Tunisian Fatimids conquered the region and created a new city as a royal enclosure for the Caliph. The area then fell into disrepair for hundreds of years and was used as a garbage dump.
Today, Fustat is part of Old Cairo, with few buildings remaining from its days as capital, though there have been many archaeological digs which have taken advantage of the wealth of buried material in the area. Many ancient items recovered from the site are on display in Cairo's Museum of Islamic Art.
The early population of the city was composed almost entirely of soldiers and their families, and the layout of the city was similar to that of a garrison: Amr intended for Fustat to serve as a base from which to conquer North Africa, as well as to launch further campaigns against Byzantium. It remained the primary base for Arab expansion in Africa until Qayrawan was founded in Tunisia in 670.
Fustat grew into a series of tribal areas, khittas, around the central mosque and administrative buildings. The majority of the settlers came from Yemen, with the next largest grouping from western Arabia, along with some Jews and Roman mercenaries. Arabic was generally the primary spoken dialect in Egypt, and was the language of written communication, though Coptic was still spoken in Fustat in the 8th century.
Fustat was the center of power in Egypt under the Umayyad dynasty, which had started with the rule of Muawiyah I, and headed the Islamic caliphate from 660 to 750. However, Egypt itself was considered only a province of larger powers, and was ruled by governors who were appointed from other Muslim centers such as Damascus, Medina, and Baghdad. The city was still a major one though, and in the 9th century, it had a population of approximately 120,000. But when General Gawhar of the Tunisian-based Fatimids captured the region, this launched a new era when Egypt was the center of its own power. Gawhar founded a new city just north of Fustat on August 8, 969, naming it Al Qahira (Cairo), and in 971, the Fatimid Caliph al-Mo'ezz moved his court from al-Mansuriya in Tunisia to the new city that Gawhar founded. But Cairo was not intended as a center of government at the time -- it stayed primarily as the royal enclosure for the Caliph and his court and army, while Fustat remained the capital in terms of economic and administrative power. The city thrived and grew, and in 987, the geographer Ibn Hawkal wrote that al-Fustat was approximately one third the size of Baghdad. By 1168, it had a population of 200,000.
The city was known for its prosperity, with shaded streets, gardens, and markets. There were reports of houses that were seven stories tall, and could accommodate hundreds of people. The Persian traveler, Nasir-i-Khusron, wrote of the exotic and beautiful wares in the Fustat markets: iridescent pottery, crystal, and many fruits and flowers available, even during the winter months. From 975 to 1075, Fustat was a major production centre for Islamic art and ceramics, and one of the wealthiest cities in the world. One report stated that it paid taxes that were equivalent to US$150,000 per day, to the administration of Caliph Mo'ezz. Modern archaeological digs have turned up artifacts from as far away as Spain, China, and Vietnam. Excavations have also revealed intricate house and street plans; a basic unit consisted of rooms built around a central courtyard, with an arcade of arches on one side of the courtyard being the principal means of access.
However, in 1168, the Christian King Amalric I of Jerusalem, who had been trying for years to launch a successful attack on Egypt in order to expand the Crusader territories, had finally achieved a certain amount of success. He and his army entered Egypt, sacked the city of Bilbeis, slaughtered nearly all of its inhabitants, and then continued on towards Fustat. Amalric and his troops camped just south of the city, and then sent a message to the young Egyptian caliph Athid, only 18 years old, to surrender the city or suffer the same fate as Bilbeis.
Seeing that Amalric's attack was imminent, Shawar ordered Fustat city burned, to keep it out of Amalric's hands. According to the Egyptian historian Al-Maqrizi (1346–1442):
Shawar ordered that Fustat be evacuated. He forced [the citizens] to leave their money and property behind and flee for their lives with their children. In the panic and chaos of the exodus, the fleeing crowd looked like a massive army of ghosts.... Some took refuge in the mosques and bathhouses...awaiting a Christian onslaught similar to the one in Bilbeis. Shawar sent 20,000 naphtha pots and 10,000 lighting bombs [mish'al] and distributed them throughout the city. Flames and smoke engulfed the city and rose to the sky in a terrifying scene. The blaze raged for 54 days....
After the destruction of Fustat, the Syrian forces arrived and successfully repelled Amalric's forces. Then with the Christians gone, the Syrians were able to conquer Egypt themselves. The untrustworthy Shawar was put to death, and the reign of the Fatimids was effectively over. The Syrian general Shirkuh was placed in power, but died due to ill health just a few months later, after which his nephew Saladin became vizier of Egypt on March 2, 1169, launching the Ayyubid dynasty.
With Fustat no more than a dying suburb, the center of government moved permanently to nearby Cairo. Saladin later attempted to unite Cairo and Fustat into one city by enclosing them in massive walls, although this proved to be largely unsuccessful.
While the Mamluks were in power from the 1200s to the 1500s, the area of Fustat was used as a rubbish dump, though it still maintained a population of thousands, with the primary crafts being those of pottery and trash-collecting. The layers of garbage accumulated over hundreds of years, and gradually the population decreased, leaving what had once been a thriving city as an effective wasteland.
The oldest-remaining building from the area is probably the Mosque of Ibn Tulun, from the 9th century, which was built while the capital was in Al-Qatta'i. The first Mosque ever built in Egypt (and by extension, the first mosque built in Africa), the Mosque of Amr, is still in use, but has been extensively rebuilt over the centuries, and nothing remains of the original structure.
It is believed that further archaeological digs could yield substantial rewards, considering that the remains of the original city are still preserved under hundreds of years of rubbish. Some archaeological excavations have taken place, the paths of streets are still visible, and some buildings have been partially-reconstructed to waist-height. But the site is difficult and dangerous to access because of the nearby slums. However, some artifacts that have been recovered so far, can be seen in Cairo's Museum of Islamic Art.