In July of 969 CE, an army commanded by the Sicilian-born general Jawhar al-Siqilli, acting on behalf of the Fatimid caliph al-Mu'izz li-Din Allah, entered Fustat, the existing Muslim capital of Egypt, after a campaign that had taken the Fatimids from their base in Ifriqiya, in present-day Tunisia, across North Africa. Rather than simply occupying Fustat, Jawhar ordered the construction of a new fortified city just to the northeast, which would be named al-Qahira, meaning "the victorious," a name later Europeanized into Cairo.
According to the traditional account, astrologers were consulted to select the precise moment to break ground, and workers hung bells on ropes strung around the site to signal the exact instant construction should begin, though the story is more often repeated than verified by contemporary sources. What is well documented is that within three years, by 972 CE, both the new city and its centerpiece mosque, al-Azhar, were substantially complete, an extraordinary pace for an urban and religious project of that scale.
The founding of Cairo took place amid a fractured and competitive Muslim world. By the mid-tenth century, the unified caliphate of the early Islamic centuries had splintered into three rival caliphates claiming legitimacy simultaneously: the Sunni Abbasids in Baghdad, whose actual political power had been eclipsed by the Buyid dynasty; the Umayyads of Cordoba in al-Andalus, who had declared their own caliphate in 929 CE; and the Ismaili Shia Fatimids, who traced their claim to leadership through descent from Fatimah, the daughter of the Prophet Muhammad, peace be upon him, and her husband Ali ibn Abi Talib.
The Fatimids had built their power base in North Africa from 909 CE onward before setting their sights on Egypt, a far wealthier and more strategically located prize connecting the Mediterranean trade routes to the Red Sea and the Indian Ocean.
Once established, Cairo quickly became more than a garrison city. Caliph al-Mu'izz himself relocated from Ifriqiya to take up residence in the new capital in 973 CE, bringing with him the treasury, the court, and even, according to several chronicles, the coffins of his Fatimid predecessors for reburial in the new city, a symbolic act asserting Cairo as the permanent seat of the dynasty. Al-Azhar mosque, completed in 972 CE, was formally established as a center of Ismaili Shia teaching by 975 CE, and within a few years it had evolved into a fully functioning institution of higher learning, with salaried scholars, structured curricula in jurisprudence and theology, and free lodging for students, arguably making it one of the oldest continuously operating universities in the world, alongside the University of al-Qarawiyyin in Fez, which had itself been founded earlier, in 859 CE, by Fatima al-Fihri.
The Islamic significance of Cairo's founding lies partly in its role as a rare and ambitious attempt to build a fully realized alternative center of Islamic religious authority. The Fatimids saw themselves not merely as regional rulers but as the rightful imams of the entire Muslim community, and al-Azhar was conceived as an instrument of that claim, training missionaries and scholars who would carry Ismaili doctrine across the Muslim world.
This is a chapter of Islamic intellectual history that is often flattened in popular narratives into a simple sectarian footnote, when in fact the scholarly infrastructure the Fatimids built, including al-Azhar and the associated Dar al-Ilm, or House of Knowledge, established later under Caliph al-Hakim in 1005 CE, produced serious work in astronomy, medicine, and philosophy that fed into the broader currents of Islamic scholarship regardless of sectarian origin.
The impact on world history is difficult to overstate given what Cairo and al-Azhar became after the Fatimid dynasty itself fell. When Salah al-Din ended Fatimid rule in 1171 CE and restored Sunni Abbasid allegiance in Egypt, he did not tear down al-Azhar; instead, over subsequent centuries under the Ayyubids, Mamluks, and Ottomans, it was gradually transformed into the preeminent center of Sunni Islamic learning that it remains today, drawing students and scholars from across the Muslim world for over a millennium.
Cairo itself grew to become the largest city in Africa and the Middle East for much of the medieval and early modern periods, a position it still occupies, and its street plan and monumental core still bear the imprint of Jawhar's original tenth-century foundation.
What mainstream world history often misses is the sheer speed and ambition of this achievement, and the degree to which a dynasty remembered primarily through a sectarian lens built institutions that transcended that sectarian identity entirely. Textbooks covering the medieval Middle East frequently jump from the Abbasid golden age directly to the Crusades and the Mongols, skipping over the Fatimid period as a minor interlude, when in fact the Fatimids governed Egypt and much of the eastern Mediterranean coast for two centuries and left behind, in al-Azhar, one of the most durable Islamic institutions ever created, one that a rival Sunni dynasty chose to preserve and repurpose rather than destroy.
For Muslims today, the story of Cairo's founding is a reminder that institutions built with genuine scholarly purpose can outlive the political projects that created them, and can be redeemed and redirected by later generations rather than discarded. Al-Azhar's transformation from an Ismaili missionary academy into the flagship of Sunni orthodoxy is an unusual example of continuity across deep doctrinal disagreement, suggesting that the value of a center of learning can, in the right hands, exceed the particular ideology of its founders.
In an era when Muslim communities often debate how to build lasting institutions, the tenth-century founders of Cairo and al-Azhar offer a case study in building for permanence, investing not just in walls and domes but in the ongoing work of teaching that a city and its scholars would carry forward for a thousand years.