Hagia Sophia (Ayasofya, Αγία Σοφία; "Holy Wisdom", Sancta Sophia or Sancta Sapientia) is a former patriarchal basilica, later a mosque, now a museum in Istanbul, Turkey. Famous in particular for its massive dome, it is considered the epitome of Byzantine architecture. It was the largest cathedral ever built in the world for nearly a thousand years, until the completion of the Seville Cathedral in 1520. The current building was originally constructed as a church between A.D. 532 and 537 on the orders of the Byzantine Emperor Justinian, and was in fact the third Church of the Holy Wisdom to occupy the site (the previous two had both been destroyed by riots). It was designed by two architects, Isidore of Miletus and Anthemius of Tralles. The Church contained a large collection of holy relics and featured, among other things, a 50 foot (15 m) silver iconostasis. It was the patriarchal church of the Patriarch of Constantinople and the religious focal point of the Eastern Orthodox Church for nearly 1000 years.
In 1453, Constantinople was conquered by the Ottoman Turks and Sultan Mehmed II ordered the building to be converted into the Ayasofya Mosque. The bells, altar, iconostasis, and sacrificial vessels were removed, and many of the mosaics were eventually plastered over. The Islamic features — such as the mihrab, the minbar, and the four minarets outside — were added over the course of its history under the Ottomans. It remained as a mosque until 1935, when it was converted into a museum by the Republic of Turkey.
For almost 500 years the principal mosque of Istanbul, Hagia Sophia served as a model for many of the Ottoman mosques such as the Sultan Ahmed Mosque (Blue Mosque of Istanbul), the Şehzade Mosque, the Süleymaniye Mosque, and the Rüstem Pasha Mosque.
Although it is sometimes referred to as Saint Sophia (Greek for wisdom), the Greek name in full is Ναός τῆς Ἁγίας τοῦ Θεοῦ Σοφίας, Church of the Holy Wisdom of God, and it was dedicated to the Holy Wisdom of God rather than a specific saint named Sophia.
Nothing remains of the first church that was built on this location, known as the Μεγάλη Ἐκκλησία (Megálē Ekklēsíā, "Great Church"), or in Latin "Magna Ecclesia".
As often happened in those days, the site was selected because there had been a pagan temple there. The church was built next to the area where the imperial palace was being developed and next to the smaller church Hagia Eirene, finished first and acting as cathedral until the Hagia Sophia was completed. The Hagia Sophia was inaugurated by Constantius II on 15 February 360. Both churches acted together as the principal churches of the Byzantine Empire.
This church was chronicled by Socrates of Constantinople (380–440), who claimed that it was built by Constantine the Great. It was built as a traditional Latin colonnaded basilica with galleries and a wooden roof. It was preceded by an atrium. This first church was then already claimed to be one of the world's most outstanding monuments.
The appellation "Megálē Ekklēsíā" continued to be used for a long time, only to be replaced by the name "Hagia Sophia" after the conquest of Byzantium in 1453.
The fire that started during the tumult of the Nika Revolt resulted in the destruction of the (second) Hagia Sophia, which burned down to the ground on 13–14 January 532.
Several marble blocks from this second church have survived to the present day, and they are displayed in the garden of the current (third) church. The blocks were originally part of a monumental front entrance; they were excavated in the western courtyard by A.M. Schneider in 1935. The relief depicting 12 lambs — 12 apostles as well as other remains of this church were discovered during excavation works in 1935. In order not to harm the present Hagia Sophia building, further excavation works were not carried out.
On February 23, 532, only a few days after the destruction of the second basilica, Emperor Justinian I took the decision to build a third and entirely different basilica, larger and more majestic than its predecessors.
Justinian chose the physicist Isidore of Miletus and the mathematician Anthemius of Tralles as architects; Anthemius, however, died within the first year. The construction is described by the Byzantine historian Procopius' On Buildings (Peri ktismatōn, Latin: De aedificiis). The emperor had material brought over from all over the empire, such as Hellenistic columns from the temple of Artemis at Ephesus. Large stones were brought from far-away quarries: porphyry from Egypt, green marble from Thessaly, black stone from the Bosporus region and yellow stone from Syria. More than ten thousand people were employed during this construction. This new church was immediately recognized as a major work of architecture, demonstrating the creative insights of the architects. They may have used the theories of Heron of Alexandria to be able to construct a huge dome over such a large open space. The emperor, together with the patriarch Eutychius, inaugurated the new basilica on December 27, 537 with much pomp and circumstance. The mosaics inside the church were, however, only completed under the reign of Emperor Justin II (565–578).
Earthquakes in August 553 and on December 14, 557 caused cracks in the main dome and the eastern half-dome to appear. The main dome collapsed completely during an earthquake on May 7, 558, destroying the ambon, the altar and the ciborium over it. The emperor ordered an immediate restoration. He entrusted it to Isodorus the Younger, nephew of Isidore of Miletus. This time he used lighter materials and elevated the dome by , thus giving the building its current interior height of . . This reconstruction, giving the church its present 6th century form, was completed in 562. The Byzantine poet Paul the Silentiary composed an extant, long epic poem, known as Ekphrasis, for the rededication of the basilica, presided over by Patriarch Eutychius, on 23 December 562.
Hagia Sophia was the seat of the Orthodox patriarch of Constantinople and a principal setting for Byzantine imperial ceremonies, such as coronations. The basilica also offered asylum to wrongdoers. Foreign visitors were deeply impressed.
In 726 the Emperor Leo the Isaurian issued a series of edicts against the veneration of images, ordering the army to destroy all icons (iconoclasm). At that time, all religious pictures and statues were removed from the Hagia Sophia. After a brief reprieve under Empress Irene (797–802), the iconoclasts made a comeback. Emperor Theophilus (829–842) was strongly influenced by Islamic art, which forbids graven images. He had a two-winged bronze door with his monograms installed at the southern entrance of the church.
After the great earthquake of 25 October 989, which ruined the great dome of Hagia Sophia, the Byzantine emperor Basil II asked for the Armenian architect Trdat, creator of the great churches of Ani and Agine, to repair the dome.. His main repairs were to the western arch and a portion of the dome. The extent of the church's destruction meant that reconstruction lasted six years. The church was re-opened on 13 May 994.
In his book De caerimoniis aulae Byzantinae (Book of Ceremonies), emperor Constantine VII (913–919) wrote about all the details of the ceremonies held in the Hagia Sophia by the emperor and the patriarch.
At the capture of Constantinople during the Fourth Crusade, the church was ransacked and desecrated by the Latin Christians. The Byzantine historian Niketas Choniates described the capture of Constantinople. Many relics from the church, such as a stone from the tomb of Jesus, the Virgin Mary's milk, the shroud of Jesus, and bones of several saints, were sent to churches in the West and can be seen now in various museums in the West. During the Latin occupation of Constantinople (1204–1261) the church became a Roman Catholic cathedral. Baldwin I of Constantinople was crowned emperor on 16 May 1204 in the Hagia Sophia, at a ceremony which closely followed Byzantine practices. Enrico Dandolo, the Doge of Venice who commanded the sack and invasion of the city by the Latin Crusaders in 1204, is buried inside the church. The tomb inscription carrying his name, which has become a part of the floor decoration, was spat upon by many of the angry Byzantines who recaptured Constantinople in 1261. However, restoration carried out during the period 1847–1849 cast doubt upon the authenticity of the doge's grave. It is more likely a symbolic burial site to keep alive his memory.
After the recapture in 1261 by the Byzantines, the church was in a dilapidated state. The four buttresses in the west were probably built during this time. In 1317, emperor Andronicus II ordered four new buttresses to be built in the eastern and northern parts of the church. After new cracks had developed in the dome after the earthquake of October 1344, several parts of the building collapsed on 19 May 1346. After that, the church remained closed until 1354, when repairs were undertaken by the architects Astras and Peralta.
Immediately after the Ottoman Turks conquered Constantinople (Istanbul) in 1453, the Hagia Sophia was converted to the Ayasofya Mosque as the symbol of the conquest. At that time, the church was very dilapidated. Several of its doors had fallen off. This condition was described by several Western visitors, such as the Córdoban nobleman Pero Tafur and the Florentine Cristoforo Buondelmonti. The sultan Mehmed II ordered the immediate cleanup of the church and its conversion to a mosque. The next sultan Bayezid II built a new minaret, replacing the one built by his father.
In the 16th century the sultan Suleiman the Magnificent (1520–1566) brought back two colossal candles from his conquest of Hungary. They were placed on both sides of the mihrab. During the reign of Selim II (1566–1577), the building started showing signs of fatigue and was extensively strengthened with the addition of structural supports to its exterior by the great Ottoman architect Sinan, who is also considered one of the world's first earthquake engineers. In addition to strengthening the historic Byzantine structure, Sinan built the two additional large minarets at the western end of the building, the original sultan's loge, and the mausoleum of Selim II to the southeast of the building (then a mosque) in 1577. The mausoleums of Murad III and Mehmed III were built next to it in the 1600s.
Sultan Mahmud I ordered the restoration of the building in 1739 and added a medrese (a Koranic school, now the library of the museum), a soup kitchen (for distribution to the poor) and a library, and in 1740 a fountain for ritual ablutions (Şadirvan), thus transforming it into a külliye, i.e. a social complex. At the same time a new sultan's gallery and a new mihrab were built inside.
The most famous restoration of the Hagia Sophia was ordered by Sultan Abdülmecid and completed by eight hundred workers between 1847 and 1849, under the supervision of the Swiss-Italian architect brothers Gaspare and Giuseppe Fossati. The brothers consolidated the dome and vaults, straightened the columns, and revised the decoration of the exterior and the interior of the building. The mosaics in the upper gallery were cleaned. The old chandeliers were replaced by new pendant ones. New gigantic circular-framed disks were hung on columns. They were inscribed with the names of Allah, the prophet Muhammad, the first four caliphs Abu Bakr, Umar, Uthman and Ali, and the two grandchildren of Mohammed: Hassan and Hussain, by the calligrapher Kazasker İzzed Effendi (1801–1877). In 1850 the architect Fossati built a new sultan's gallery in a Neo-Byzantine style connected to the royal pavilion behind the mosque. Outside the Hagia Sophia, a timekeeper's building and a new medrese were built. The minarets were altered so that they were of equal height. When the restoration was finished, the mosque was re-opened with ceremonial pomp on 13 July 1849.
Hagia Sophia is one of the greatest surviving examples of Byzantine architecture. Of great artistic value was its decorated interior with mosaics and marble pillars and coverings. The temple itself was so richly and artistically decorated that Justinian proclaimed, "Solomon, I have surpassed thee!" (Νενίκηκά σε Σολομών). Justinian himself had overseen the completion of the greatest cathedral ever built up to that time, and it was to remain the largest cathedral for 1,000 years up until the completion of the cathedral in Seville in Spain.
Justinian's basilica was at once the culminating architectural achievement of late antiquity and the first masterpiece of Byzantine architecture. Its influence, both architecturally and liturgically, was widespread and enduring in the Eastern Orthodox, Roman Catholic, and Muslim worlds alike. The largest columns are about 19 or 20 meters tall. They are at least 1.5 meters diameter. They are made out of granite. the largest weigh well over 70 tons. For more on the columns see the talk section. Under Justinian's orders, eight Corinthian columns were disassembled from Baalbek, Lebanon and shipped to Constantinople for the construction of Hagia Sophia.
The vast interior has a complex structure. The vast nave is covered by a central dome which has a maximum diameter of and a height from floor level of , about one fourth smaller than the dome of the Pantheon. The dome seems rendered weightless by the unbroken arcade of 40 arched windows under it, which help flood the colourful interior with light. Due to consecutive repairs in the course of its history, the dome has lost its perfect circular base and has become somewhat elliptical with a diameter varying between and .
The dome is carried on pendentives — four concave triangular sections of masonry which solve the problem of setting the circular base of a dome on a rectangular base. At Hagia Sophia the weight of the dome passes through the pendentives to four massive piers at the corners. Between them the dome seems to float upon four great arches. These were reinforced with buttresses during Ottoman times, under the guidance of the architect Sinan.
At the western (entrance) and eastern (liturgical) ends, the arched openings are extended by half domes carried on smaller semi-domed exedras. Thus a hierarchy of dome-headed elements builds up to create a vast oblong interior crowned by the main dome, a sequence unexampled in antiquity. Despite all these measures, the weight of the dome remained a problem, which was solved by adding buttresses from the outside.
All interior surfaces are sheathed with polychrome marbles, green and white with purple porphyry and gold mosaics, encrusted upon the brick. This sheathing camouflaged the large pillars, giving them, at the same time, a brighter aspect.
On the exterior, simple stuccoed walls reveal the clarity of massed vaults and domes. The yellow and red colour of the exterior was added by the architect Fossati during the restorations in the 19th century.
Although this design stabilizes the dome and the surrounding walls and arches, the actual construction of the walls of Hagia Sophia weakened the overall structure. The bricklayers used more mortar than brick, which weakened the walls. The structure would have been more stable if the builders at least let the mortar cure before they began the next layer; however, they did not do this. When the dome was placed atop the building, the weight of the dome caused the walls to lean outward because of the wet mortar underneath. When Isidorus the Younger rebuilt the original dome, he had to first build up the interior of the walls so that they were vertical in order to support the weight of the new dome. Another probable change in the design of the dome when it was rebuilt was the actual height of the dome. Isidore the Younger raised the height of the dome by approximately twenty feet so that the lateral forces would not be as strong and the weight of the dome would flow more easily down the walls.
A second interesting fact about the original structure of the dome was how the architects were able to place forty windows around the base of the dome. Hagia Sophia is famous for the mystical quality of light that reflects everywhere in the interior of the nave, which gives the dome the appearance of hovering above the nave. This design is possible because the dome is shaped like a scalloped shell or the inside of an umbrella with ribs that extend from the top of the dome down to the base. These ribs allow the weight of the dome to flow between the windows, down the pendentives, and ultimately to the foundation.
The unique character of the design of Hagia Sophia show how this structure is one of the most advanced and ambitious monuments of late antiquity.
The Imperial Gate was the main entrance between the exo- and esonarthex. It was reserved only for the emperor. The Byzantine mosaic above the portal depicts Christ and Emperor Leo VI the Wise.
A long ramp from the northern part of the outer narthex leads up to the upper gallery.
The Loge of the Empress is located in the centre of the upper enclosure, or gallery, of the Hagia Sophia. From there the empress and the court-ladies would watch the proceedings down below. A round, green stone marks the spot where the throne of the empress stood.
The Marble Door inside the Hagia Sophia is located in the southern upper enclosure, or gallery. It was used by the participants in synods, they entered and left the meeting chamber through this door.
The church was richly decorated with mosaics throughout the centuries. They either depicted the Virgin Mother, Jesus, Saints, or emperors and empresses. Other parts were decorated in a purely decorative style with geometric patterns.
During the Sack of Constantinople in 1204, the Latin Crusaders vandalized the valuable items in every important Byzantine structure of the city, including the golden mosaics of the Hagia Sophia. Much of these valuable items were shipped to Venice, whose Doge, Enrico Dandolo, had organized the invasion and sack of Constantinople.
Following the building's conversion into a mosque in 1453, many of its mosaics were destroyed or covered with plaster, due to Islam's ban on representational imagery. This process was not completed at once, and reports exist from the 17th century in which travellers note that they could still see Christian images in the former church. In 1847–49, the building was restored by two Swiss brothers, Gaspare and Giuseppe Fossati, and Sultan Abdülmecid allowed them to also document any mosaics they might discover during this process. This work did not include repairing the mosaics and after recording the details about an image, the Fossatis painted it over again. This work included covering the previously uncovered faces of two seraphim mosaics located in the centre of the building. The building currently features a total of four of these images and two of them are restorations in paint created by the Fossatis to replace two images of which they could find no surviving remains. In other cases, the Fossatis recreated damaged decorative mosaic patterns in paint, sometimes redesigning them in the process. The Fossati records are the primary sources about a number of mosaic images now believed to have been completely or partially destroyed in an earthquake in 1894. These include a great mosaic of Christ Pantocrator in the dome, a mosaic over a now unidentified Door of the Poor, a large image of a jewel-encrusted cross and a large number of images of angels, saints, patriarchs, and church fathers. Most of the missing images were located in the building's two tympana. The Fossatis also added a pulpit (minbar) and the four large medallions on the walls of the nave bearing the names of Muhammad and Islam's first caliphs.
A large number of mosaics were uncovered in the 1930s by a team from the American Byzantine Institute led by Thomas Whittemore. The team chose to let a number of simple cross images remain covered by plaster, but uncovered all major mosaics found.
Due to its long history as both a church and a mosque, a particular challenge arises in the restoration process. The Christian iconographic mosaics are being gradually uncovered. However, in order to do so, important, historic Islamic art would have to be destroyed. Restorers have attempted to maintain a balance between both Christian and Islamic cultures. In particular, much controversy rests upon whether the Islamic calligraphy on the dome of the cathedral should be removed, in order to permit the underlying Pantocrator mosaic of Christ as Master of the World, to be exhibited (assuming the mosaic still exists).