Over the course of its long history, the building dedicated to Holy Wisdom—Hagia Sophia—has changed hands between Christians and Muslims and even became a secular institution in the last century. The recent decision to reconvert the monument to a mosque cannot be without its consequences—physical, cultural, religious, ideological, and symbolic. From church to mosque to museum, and now back to mosque, Hagia Sophia has come to mean so much to so many; it has become a culturally prismatic icon. And its preservation in its myriad forms should continue.

Hagia Sophia, Istanbul/Constantinople, 532-537. (Courtesy of Haluk Comertel/Wikimedia

Built as an imperial Christian church in Constantinople, now Istanbul, by Emperor Justinian I (r. 527–565), Hagia Sophia replaced an earlier religious building on the site that was damaged during the Nika Revolt of 532. Justinian’s new church was dedicated in 537, and it served from the outset as a symbol of imperial power in Constantinople and throughout the world. Architects Anthemios of Tralles and Isidore of Miletus ingeniously designed the building. Their engineering feat successfully juxtaposed a longitudinal basilican plan characteristic of Western Christian churches with a centralized one often found in martyria, mausolea, baptisteries, and pilgrimage churches. As such, in its layout, Hagia Sophia was designed with a narthex, a naos with side aisles, and a semicircular apse facing east. Its multi-story elevation consists of a gallery above the side aisles, half domes, and the main dome above. Rising about 184 feet over the central naos and measuring about 120 feet in diameter, this monumental dome appears as if suspended from the heavens. The impression is further accentuated by the 40 windows that circle its base, which allow light in and contribute to the dematerialization of its surface and architectonic structure.

Interior view, Hagia Sophia. (Courtesy of Dean Strelau/Wikimedia Commons)
View of the apse, Hagia Sophia. (Courtesy of Christophe Meneboeuf/Wikimedia Commons)

In addition to its impressive architecture, Hagia Sophia also exhibited an interior decorated with marble revetments on the floor and the lower sections of the walls, spoliated columns, intricate carvings, as well as lavish mosaic decorations reserved for the upper sections and the galleries. The interior thus offered a sensorially-rich experience further enhanced during the liturgical and paraliturgical celebrations by movements, sounds and music, incense, and various light effects. The architecture of the building, its rich decorations, and ritual performances helped enhance the other-worldly experience unfolding within, intended to bring the faithful closer to the divine. Although its original spiritual purpose has ended, its physical and symbolic ones carry on.

The extant mosaic decorations of Hagia Sophia postdate the 9th-century iconoclastic period in Byzantium during which the function of figurative Christian imagery was hotly debated and the building’s decorative scheme was transformed. The Virgin and Christ Child mosaic in the apse is regarded as the first post-iconoclastic figural image to be set up in the building, although it was restored in the 14th century. It likely replaced a large cross that was set in the apse during the iconoclastic period. Monumental in scale, the figures of the Virgin and Child appear dwarfed by their gold background and the impressive surrounding architecture. Images of the archangels Gabriel and Michael on the arch of the apse frame this important central duo.

Donor Mosaics, entrance into the narthex, Hagia Sophia. (Courtesy of Mattias Hill/Wikimedia Commons)

Additional mosaics include donor portraits commissioned by Byzantine rulers at various moments throughout the history of the empire to commemorate their support of Hagia Sophia. Most notable, the tympanum of the imperial gate leading into the building preserves a mosaic of Emperor Leo VI (r. 886–912) kneeling before Christ, and the tympanum of the south entrance into the narthex shows the “Mosaics of the Donors”—emperors Justinian and Constantine offering a model of Hagia Sophia and the city of Constantinople, respectively, to the enthroned Virgin and Child. The galleries display other exquisite donor portraits in mosaic from the 10th and 11th centuries. These images, found in prominent locations within the building, were meant to be regularly seen and addressed in the context of liturgical and para-liturgical celebrations. They offer a visual testimony of the new ktetors or founders of the building and models for how future generations ought to care for the monument.  

Over the course of its long history, Hagia Sophia experienced a series of transformations that affected its structure and decorations. The iconoclastic controversies of the 8th and 9th centuries stripped the building of its figural religious images and sculptural works. The still existing mosaics postdate this moment. After the Fourth Crusade in 1204 the building was converted to Roman Catholic use. It became an Eastern Orthodox Church again only in 1261 when the Byzantines recaptured Constantinople from the Latins. But the most transformative moment came in 1453 when the Ottoman Turks under the leadership of Sultan Mehmed II “the Conqueror” (r. 1444–1446; 1451–1481) besieged Constantinople and brought an end to the Byzantine Empire. 

Hagia Sophia was converted into a mosque. Minarets were built on the exterior and a minbar and a mihrab in the naos. In the interior, moreover, the Christian furnishings were removed, and the decorations eventually whitewashed or plastered over. In their place, geometric designs and intricate wooden carvings were set up. Later, giant circular framed disks inscribed with the names of Allah, Prophet Mohammed, the first four caliphs (Abu Bakr, Umar, Uthman, and Ali), and the two grandchildren of Mohammed, Hassan and Hussain, were installed in the naos. Around its exterior, the building received royal tombs for Ottoman sultans. Although Hagia Sophia remains a kind of anomaly in the history of architecture, its distinct features have informed the design of Eastern Orthodox churches throughout the medieval period and that of mosques after 1453.

Thomas Whittemore and his team uncover the 10th century mosaics of Saint John Chrysostom (left) and Saint Ignatius Theophorus in the north tympanum of Hagia Sophia. (Courtesy of John Sanidopoulos)

During the mid-19th century, interest in the history and decorations of Hagia Sophia peaked. In 1847, by order of the Sultan Abdulmejid I (r. 1839–1861), the Swiss-Italian brothers Gaspare and Giuseppe Fossati embarked on a restoration project of Hagia Sophia. Their work over the course of two years also involved the uncovering and recording of the Christian images, after which they were concealed once again. The Fossati brothers’ files document details of the mosaics and works subsequently destroyed, including some in the earthquake of July 10, 1894. Further restorations carried out in the 1930s under the supervision of Thomas Whittemore uncovered more of the mosaics, which were to be preserved as Hagia Sophia entered its new phase of existence. The arduous work of recovering the mosaics continued until 1935 when the building opened to the world as a museum. The official order came the previous year, on November 24, 1934, under the leadership of Turkey’s first president, Mustafa Kemal Atatürk (1881–1938). Additional restorations were aimed at safeguarding both the Christian and Islamic pasts of Hagia Sophia. Its historical and universal value took center stage. 

As a secular and public institution, Justinian’s church and Mehmed’s mosque was thus transformed into a symbol of secular modernity for Turkey. Its new function was to offer the millions of visitors each year insights into its long history, ingenious architecture, furnishings, and beautiful decorations. The recent change to reconvert Hagia Sophia into a mosque threatens all of this. 

The main concern, among art historians and conservators in particular, is the future of the figurative mosaic decorations that are preserved in the upper portions of the building, as well as concerns with possible moisture and mold under the teal wool wall-to-wall carpets that are currently being layered on top of the marble floors. Interestingly, the section of the flooring that was deliberately left uncovered by the carpets is the colorful marble omphalion (“little navel [of the earth]”) located in the south-east quarter of the main square beneath the central dome—the spot where the Byzantine emperors were crowned during the coronation ceremony. 

Omphalion of Hagia Sophia where the Byzantine emperors were crowned. (Courtesy of Ian Scott/Wikimedia Commons)

Solutions for concealing the mosaics have included laser projections or curtains. It appears that the latter has been chosen as a less invasive and expeditious option, at least for the time being. Now, great swaths of white cloth obscure the Virgin and Child in the apse. Supposedly, the curtains could be removed for those who wish to see the Christian mosaics outside of Muslim prayers times, but the details of such maneuvering remain to be determined.   

Although scholars, theologians, and other leaders have commented on the recent reconversion of the building, no statement has been as critical as that of UNESCO. Hagia Sophia became an UNESCO World Heritage Site in 1985 and, therefore, any decision regarding the monument should have been made in consultation and dialogue with UNESCO and experts to ensure the proper care of the building. The Christian, Islamic, and secular pasts of Hagia Sophia ought to be preserved for current and future generations so that all who have the privilege of experiencing this magnificent building can appreciate its competing layers of history and meaning. Despite its recent change in function, Hagia Sophia remains an extraordinary monument—an unicum in world architecture.

A Christian church for almost 1000 years, a mosque for close to 500 years, a museum for 85 years, and now once again a mosque. Hagia Sophia has experienced a lot, and there is still more future ahead.

Alice Isabella Sullivan, Assistant Professor of Medieval Art and Architecture at Tufts University, is an award-winning author and co-founder of North of Byzantium.