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Sergius and Bacchus

The Monastery of Saints Sergius and Bacchus at Hormisdas (Μονὴ τῶν Άγίων Σεργίου καί Βάκχου ὲν τοῖς Ὸρμίσδου) was built during the reign of Justinian. It is located near the Sea Wall by the Marmara Sea south of the Hippodrome of Constantinople. It was built on the grounds of the Palace of Hormisdas next to the Basilica of Sts. Peter and Paul. The church was dedicated to the saints Sergius and Bacchus, Roman soldiers who were martyred under Emperor Maximian around 300. Its association with Hagia Sophia is reflected in its Turkish name, Küçük Ayasofya Camii (“Little Hagia Sophia Mosque”).

The Church of Ss. Sergius and Bacchus was built on the grounds of the Palace of Hormisdas, which was named after a Sassanid prince who was received at the court of Emperor Constantine after fleeing from Persia in 324. The palace was the residence of Justinian when his uncle Justin I (518-527) was the ruling emperor. After consecrated the Basilica of Ss. Peter and Paul at the palace in 518-519, he asked Pope Hormisdas for the relics of the two apostles in Rome. The precise date of Sergius and Bacchus is controversial. Traditionally it was been argued that it was a palatine chapel built by Justinian and Theodora built around 527 when the imperial couple moved to the Great Palace complex. However, it has also been argued that it was built by the year 536 for Syrian Monophysite monks who were being supported by Empress Theodora. It is known that the palace accommodated over 500 Monophysite refugees during this period. The church was first attested – as a monastery under Abbot Paul – in 536 when the anti-Monophysite council of 536 was held here. Following the death of Theodora in 548, its Monophysite inhabitants were moved to the house of Urbicius. Around 547, Pope Vigilius, fearing Justinian’s wrath during the Three Chapters Controversy (related to the Nestorian heresy), sought refuge at the monastery and attempts to remove him by force failed due to the protests of the populace. It also has stylistic affinities with the Church of St. Polyeuctus built by Anicia Juliana built a short time earlier.

This church remained a monastery throughout the Byzantine era. The church was a center of Iconoclasm under its hegoumenos (abbot) and future Patriarch John VII Grammatikos during the reigns of Leo V and Theophilus. As hegoumenos (c. 815-37) he interrogated many prominent supporters of icons, including Theodore of Stoudios and Theophanes the Confessor, at Sergius and Bacchus. Sergius and Bacchus was restored by Basil I after 867 and was granted to the See of Rome in 880 during the reign of Basil I, though it seems to have already been placed in the service of the Pope earlier. The future Patraich Euthymios rejected Leo VI’s attempt to make him the hegoumenos. Its fate during the Latin occupation of the city is unknown, but it is mentioned by pilgrims visiting the city following the Byzantine reconquest of the city in 1261. In the early 16th century, the church was converted into a mosque by Hüseyin Agha, the chief eunuch of the harem of Bayezid II. His türbe (tomb) is now in the middle of the cemetery north of the mosque, which is often named after him as well. The building was restored in 1740 and again after the fire of 1758. It housed refugees from the Balkan in the early 20th century and was restored again in 1956.

Serigus and Bacchus, along with its more famous and impressive counterpart Hagia Sophia, reveals the inventiveness of Justinian’s construction projects in Constantinople. It has often been considered an important precursor of Hagia Sophia, but as its date is controversial, this is far from certain. It shared the same atrium with the adjacent church of Ss. Peter and Paul that was probably a basilica. It has been argued that this accounts for its irregular plan. While it is not very large (measuring around 30 x 34 meters), it is designed in such a way that produces a sense of spaciousness inside. This structure can be compared with the churches of San Vitale in Ravenna and the non-extant St. John Prodromos at Hebdomon.

The brick-and-mortar building has an octagonal nave set within a irregular rectangle. It has a double-storied arcade that supporting a pumpkin dome (17 meters in diameter) with 16 alternating curved and flat wedges. The flat surfaces are pierced by windows, while the curved wedges coincide with the corners of the octagon. There is a broad arch over the apse on its east side and seven narrower arches over the other piers. The arches of the octagon frame two-story niches of alternating rectangular and semicircular plan, while the angles of the octagonal nave are marked by eight wedge-shaped piers. Paired columns of verde antico and red-veined Synnada marble support a richly carved horizontal entablature made of Proconnesian marble at the gallery level. These columns are capped with delicately undercut “melon” or “folded” capitals, which emphasize the crosses and imperial monograms in the center. The columns of the gallery also include Ionic impost capitals. Along its entire length is an inscribed epigram with expertly carved letters in honor of Justinian and Theodora. The entablature also includes the traditional egg-and-dart, bead-and-reel and acanthus rinceau. While it would have originally been decorated with mosaics and polychrome marble revetment on its walls and piers, it is now mostly covered with plaster. During the Ottoman era, additions include a portico at the entrance and a minaret, while the dome was sheathed in lead and the windows were altered. A tekke (sufi lodge) with thirty-six chambers was founded around the mosque, while a fountain was built in its courtyard.

Church of SS Sergius and Bacchus (Küçük
Church of SS Sergius and Bacchus (Küçük
Church of SS Sergius and Bacchus (Küçük


[Ἄλλοι μὲν βα]σιλῆες ἐτιμήσαντο θανόντας

ἀνέρας, ὧν ἀνόνητος ἔην πόνος· ἡμέτερος δὲ

εὐσεβίην σκηπτοῦχος Ἰουστινιανὸς ἀέξων

Σέργιον αἰγλήεντι δόμῳ θεράποντα γεραίρει

5         Χριστοῦ παγγενέταο· τὸν οὐ πυρὸς ἀτμὸς ἀνάπτων,

οὐ ξίφος, οὐχ ἑτέρη βασάνων ἐτάραξεν ἀνάγκη,

ἀλλὰ θεοῦ τέτληκεν ὑπὲρ Χριστοῖο δαμῆναι

αἵματι κερδαίνων δόμον οὐρανόν. ἀλλ᾽ ἐνὶ πᾶσιν

κοιρανίην βασιλῆος ἀκοιμήτοιο φυλάξοι

10      καὶ κράτος αὐξήσειε θεοστεφέος Θεοδώρης,

ἧς νόος εὐσεβίῃ φαιδρύνεται, ἧς πόνος ἀεὶ

ἀκτεάνων θρεπτῆρες ἀφειδέες εἰσὶν ἀγῶνες.


Other sovereigns have honored dead men whose labor was unprofitable, but our sceptered Justinian, fostering piety, honors with a splendid abode the Servant of Christ, Begetter of all things, Sergius; whom not the burning breath of fire, nor the sword, nor any other constraint of torments disturbed; but who endured to be slain for the sake of Christ, the God, gaining by his blood heaven as his home. May he in all things guard the rule of the sleepless sovereign and increase the power of the God-crowned Theodora whose mind is adorned with piety, whose constant toil lies in unsparing efforts to nourish the destitute.                                  (Translated by Cyril Mango)

Church of SS Sergius and Bacchus (Küçük
Church of SS Sergius and Bacchus (Küçük
Basilica of San Vitale.jpg

Mosaics of Justinian and Theodora in San Vitale


The monograms of Justinian, Theodora and basileos (emperor) at Sergius and Bacchus are box monograms. The monograms of Justinian (IOYCTINIANOY) are based on the letter N, with the letter I contained in its upright. Both the letters T and a square C (Sigma) are to the right, with the letter A inserted within the left side of the N (in more than one variation), and the OY diphthong crowning the monogram. The monograms of Theodora (ΘEOΔѠPAC) are based around P (Rho) and E, with the Ѡ (Omega) on the verticals, Θ (Theta) as the center letter (with incorporated letter O), and the A at the bottom. In some cases the Δ is formed by added a bar beneath the A. There are also monograms of ΒΑCΙΛΕѠΣ (basileos) based on B and E with Ѡ (Omega) above.

Sergius and Bacchus.jpg
Sergius and Bacchus.jpg

From Buildings by Procopius

His faith in the Apostles of Christ he displayed in the following manner. First he built a church of Peter and Paul, which had not previously existed in Byzantium, alongside the imperial residence which in former times was called by the name of Hormisdas. For he had contrived that this building, which was his private residence, should both seem to be a palace, and by the magnificence of its structure be as handsome as one; and when he became Emperor of the Romans he joined it to the Palace proper. There too he built another shrine to the famous Saints Sergius and Bacchus, and then also another shrine which stood at an angle to this one. These two churches do not face each other, but stand at an angle to one another, being at the same time joined to each other and rivalling each other; and they share the same entrances and are like each other in all respects, even to the open spaces by which they are surrounded; and each of them is found to be neither superior nor inferior to the other either in beauty or in size or in any other respect.  Indeed each equally outshines the sun by the gleam of its stones, and each is equally adorned throughout with an abundance of gold and teems with offerings. In just one respect, however, they do differ. For the long axis of one of them is built straight, while in the other church the columns stand for the most part in a semi-circle. But whereas they possess a single colonnaded stoa, called a narthex because of its great length, for each one of their porches, they have their propylaea entirely in common, and they share a single court, and the same doors leading in from the court, and they are alike in that they belong to the Palace. These two churches are so admirable that they manifestly form an adornment of the whole city, and not merely of the Palace.

 Küçük Ayasofya Mosque.jpg
Marble Transenna from San Vitale.jpg

Marble Transennae (a) from mimbar of Little Hagia Sophia Mosque (b) from San Vitale National Museum of Ravenna

Sergius and Bacchus.jpg

Icon of Saints Sergius and Bacchus,

Sinai, seven-century 

Khanenko Museum in Kyiv


Aerial photos by Kadir Kır


Aerial photos by István Pi Tóth

From The Book of Ceremonies by Constantine Porphyrogennetos

The emperor goes out into the Hippodrome, escorted by all of these and those mentioned previously, and goes through the Hippodrome while the crowds of people stand in the Hippodrome praying for the emperor. Escorted by everyone, the emperor goes through the Old Imperial Bureaux and goes away into the Church of St Sergios.

When the emperor is about to go into the gallery, the patricians and strategoi remain outside the door, and the abbot of the said church receives the emperor there near the door, carrying a censer and censing in front of the emperor. The emperor, having gone into the gallery, lights candles opposite the sanctuary above the imperial doors and prays there. Having prayed in the Chapel of the Most Holy Theotokos which is in the gallery, and having lit candles there and prayed, he goes out and stands in the private box of the sanctuary where it is usual for him to stand for each procession and to participate in the divine liturgy, and he lights candles there.


From The Chronicle of Theophanes Confessor

[In 546/47] Pope Vigilius arrived in Constantinople and after being received with great honour by the emperor, he promised to unite the catholic Church and anathematize the Three Chapters. He was so greatly honoured by the emperor that he became puffed up and excommunicated Menas, bishop of Constantinople, for four months by way of penance. Menas replied by imposing the same penance on Vigilius. The emperor, annoyed by Vigilius because of the penance and the delay in fulfilling his promises about uniting the Church, dispatched men to arrest him. Vigilius, fearing the emperor's wrath, sought refuge in the sanctuary of Sergius the martyr in the monastery of Hormisdas. As he was being dragged from there, he held on to the columns supporting the altar, and brought them down, for he was a large heavy man. The emperor repented and received Pope Vigilius who, in turn, at the request of the Augusta Theodora, received Menas, patriarch of Constantinople, on 29 June, the day of the Holy Apostles.


Photos by Sébah


Photos by Sébah & Joaillier

Sergius and Bacchus.jpg

From Byzantine Studies by Paspates (1877)

Ebersolt & Thiers (2).jpg

Ebersolt & Thiers (1910)


Plan by Müller-Wiener

Basilica of San Vitale.jpg

Reconstructed marble revetment and floors of the naos


Plan of San Vitale


Plan of St. John Prodromos at Hebdomon by Mathews



“The Church of Sts. Sergius and Bacchus One Again” by Cyril Mango

“The Church of Sts. Sergius and Bacchus in Constantinople and the Monophysite Refugees” by Jonathan Bardill 

“Monograms on the Capitals of S. Sergius at Constantinople” by H. Swainson

“Justinian, Theodora, and the Church of Saints Sergius and Bacchus” by Brian Croke

Byzantine Architecture by Cyril Mango

Brickstamps of Constantinople by Jonathan Bardill

Bildlexikon zur Topographie Istanbuls: Byzantion, Konstantinupolis, Istanbul by Müller-Wiener

Byzantine Churches in Constantinople: Their History and Architecture by Alexander Van Millingen

La géographie ecclésiastique de l'Empire byzantin by R. Janin

Les Eglises de Constantinople by Ebersolt and Thiers

Converted Byzantine Churches in Istanbul: Their Transformation Into Mosques and Masjids by S. Kirimtayif

Oxford Dictionary of Byzantium edited by Alexander Kazhdan

The Oxford Handbook of Byzantine Studies edited by Cormack, Haldon, & Jeffreys

The Cambridge Companion to the Age of Justinian edited by Michael Maas

Age of Spirituality Late Antique And Early Christian Art Third To Seventh Century (MET)

Primary Sources

Buildings by Procopius translated by H.B. Dewing

The Book of Ceremonies by Constantine Porphyrogennetos (translated by Moffatt and Maxeme Tall)

The Chronicle of John Malalas

The Chronicle of Theophanes Confessor translated by Mango, Scott, & Greatrex


Sergius and Bacchus Photo Album (Byzantine Legacy Flickr)

Byzantine Churches of Constantinople (Byzantine Legacy Google Map)

Saints Sergios and Bacchos (Byzantium 1200)

Sts. Sergius and Bacchus (Nicholas V. Artamonoff Collection)

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