1. The architecture before Justinian
1.1. Basilica: the main architectural type
The religious architecture of the 4th century is generally characterized by a variety of architectural combinations, since there is an effort of adapting known architectural forms to the liturgical needs of a new religion. Nevertheless, from the second half of that century, the became the predominant building type, since the opportunity for great size that this particular type offered corresponded to the need for a spacious internal area of the buildings dedicated to the Christian worship, where the attendance to the liturgy demanded the gathering of the faithful.
About the choice of the basilica as the place for the Christian worship many suggestions have been made. Sometimes the role of Constantine himself in this choice is overestimated; it is, however, highly possible that the imperial symbolism of the basilica as a Roman public building were bequeathed to the Christian variation of the type, especially on these cases, where, as it largely happened in Constantinople, the Christian churches were imperial foundations as well.1 In a general way, however, the choice and the formation of this architectural type is interpreted by the researchers with regard to the needs that dictated the formalization of the liturgical ritual through the embodiment of many elements from the Roman imperial ritual.2 Although it is about a plausible hypothesis, not all the researchers agree with the functionality of the basilica, how much more since we largely ignore the ritual of the early Byzantine liturgy.3
1.2. The monuments of the 4th century
It seems that Constantine (307-337) never really developed in Constantinople a real program of Christian edifices, as he had done in the case of Jerusalem. In various later sources many edifices are attributed to Constantine the Great (besides Hagia Eirene, Holy Apostles and Hagia Sophia are mentioned as well Saint Akakios, which was destroyed and rebuilt at the beginnings of the 5th century, the basilica-martyrium of Saint Mokios, Saint Agathonikos, Saint Menas, Michaelion of Anaplous and Hagia Dynamis); it seems, however, that these were later attempts to underline the oldness or the greatness of certain monuments through their connection with Constantine, or to attribute a Christian building program to Constantine equivalent either to that of Theodosios II and Pulcheria or, much more, to that of Justinian I.4
Generally the churches of the 4th century, besides the one of Hagia Eirene, must be attributed to Constantine’s successors. In any way, nothing has been preserved from the churches of that period in Constantinople, and few conclusions can be deduced in reference to their architecture. There must have been a relative variety of form in relation to the characteristics and the arrangement of the basilicas. The example of the Holy Apostles, a cruciform church according to the most prevalent view, attests eventually that the quest in the religious architecture was not only towards the direction of the formalization of a certain type, but towards the search of new forms as well.
Hagia Eirene, the first cathedral of the new capital, very close to the complex of the palaces and the Hippodrome, must have been a timber-roofed basilica. In every probability it was enclosed within the same precinct with the slightly later church of Hagia Sophia. It was destroyed during the Nika Riot in 532 and was rebuilt within the framework of the building program of Justinian I. The Great Church, as the first church of Hagia Sophia was named, was also a timber-roofed basilica, possibly five-, with and probably an on the west side.5 This church was consecrated in 360 by Constantius II (337-361). It was destroyed by fire in 404.6 In 415 the new church of Hagia Sophia was consecrated, having been repaired by Theodosios II.
The church of the Holy Apostles,7 near the spot where the northwestern branch of the Mese met the Constantinian wall of the city, was also rebuilt in 536-550 by Justinian I. In the older bibliography the church is sometimes mentioned as the one that introduced a new type of a cruciform martyrium, but the conclusions of modern research do not support this opinion. The Constantinian edifice that was indeed intended, according to Eusebios, to serve as the mausoleum of the emperor and at the same time as the martyrium of the Apostles (since it was the pursuit of Constantine to be worshipped as the thirteenth Apostle in a Christianized edition of the post mortem consecration of the Roman emperor) was in all probability a circular (or an octagonal) building, something that was not usual in the typology of the mausoleums and the martyria.
During the reign of Constantius II a church was built by the mausoleum of Constantine, separating the imperial mausoleum from the church of the Holy Apostles. We guess that this second building was cruciform with arms of the same length, each one of which being a longitudinal, maybe three-aisled basilica.8 The whole complex was situated at the center of a big court and was surrounded by meeting halls and baths. Eusebios describes the inner decoration of the churches as lavish, with a gilded ceiling and wall .
1.3. The monuments of the 5th century
Under Theodosios II (408-450) the building of monasteries and churches in Constantinople was intensified. Notitia Urbis Constantinopolitanae, composed in all probability during the second quarter of the 5th century, lists fourteen churches in the city.9 However, important remains of only few of the basilicas from the 5th century are preserved. It is mainly about the Stoudios basilica (Imrahor Camii), which was the katholikon of the monastery of Akoimetoi, in the district of Psamathias, near the shores of the Sea of Marmara and to the northeast of the Golden Gate of the Theodosian land walls. The church was dedicated to Saint John the Baptist. It was founded by the senator John Stoudios around the middle of the 5th century.10 Although ruined, it still preserves many elements of its original form and upper structure that help us reconstruct a clear picture of it. It was a with galleries, an atrium and a . The longitudinal axis is merely emphasized in relation to its width, resulting in a ground-plan almost square in shape.
From the also three-aisled basilica of the Theotokos of Chalcoprateia,11 situated near Hagia Sophia, very few remains are preserved. It was a basilica with many similarities to the one of Stoudios, although clearly of greater overall dimensions. Here as well the proportions create an almost square-in-shape ground plan. On the northwest corner of the atrium an octagonal construction was annexed, probably a baptistery. Another basilica which seems that followed the same plan had been excavated in the court-yard of Topkapı Saray.12 Of smaller overall dimensions than the other two, it followed the same proportions and most probably a similar arrangement. The traces of a and an were excavated, providing one of the earliest examples of this kind of liturgical constructions in the church architecture of the capital.
The Hagia Sophia of Theodosian date,13 destroyed by fire during the Nika Riot in 532, was a five-aisled basilica with galleries. The west side of the entrance was being formed with a monumental , parts of which have been excavated, whereas in the northeast corner of the church stood a separated, central-plan building that probably served as a . For these remains of the pre-Justinianic church, although it is generally considered that they belong to the Theodosian church, a dating earlier in the 4th century has also been supported. The wall masonry, exclusively made of brick stones, could eventually go back to the Constantinian period, but the difference from the alternation of courses of blocks of stones and bricks that we find in the wall masonry of the Theodosian land wall of Constantinople is not enough in order to support such a dating, since the pure brick masonry is found in the Theotokos of Chalcoprateia, dated in the 5th century.
1.4. General conclusions
For the 4th century, from which no monuments are preserved, we can only make some conjenctures. During the 5th century, however, it seems that some characteristics were being formalized in reference to the Constantinopolitan basilicas. The main entrance at the west side was emphasized through an atrium (Stoudios basilica, Theotokos of Chalcoprateia) or, in the case of Hagia Sophia , through a monumental porch. In the Topkapı basilica the atrium was replaced by a courtyard, slightly displaced in reference to the axis of the church.
The narthex became a standard element of the basilica, since we find it in all three basilicas of which we have on our disposal the ground-plan. In the Stoudios basilica and the Theotokos of Chalcoprateia we recognize an earlier stage in the development of this architectural element, since it is the eastern part of the atrium that was being formed as a narthex,14 whereas in the Topkapı basilica the narthex is already independent from the courtyard and attached to the church.
The galleries seem to have existed in at least three out of the four cases, and in the Topkapı basilica, where we can not be certain about their existence, the walls were thick enough to support the weight.15 In addition, in the Stoudios basilica, where part of the galleries survive, we see that the faithful had no access to these from the interior, but through staircases from the outside of the church.
On the eastern side of the basilicas comes up the , three-sided (Stoudios basilica, Theotokos of Chalcoprateia) or five-sided (Topkapı basilica) on the outer face and semicircular on the inner face. There are not, however, any pastophoria or parabemata to flank the apse. In Hagia Sophia what is described as skeuophylakion (and which has survived from the pre-Justinianic phase of the monument) is a separated central-plan building with an irregular twelve-sided-in-shape ground plan on the northeast corner of the church.16 An interesting element is that on both sides of the apse on the eastern wall of the Constantinopolitan basilicas entrances were opened towards the north and the south aisle respectively, entrances that are marked on the ground plan of the Stoudios basilica and of Theotokos of Chalcoprateia.
Inside the basilica, the area of the sanctuary is marked by the . In the Stoudios basilica this was made of stone; the Π in shape stylobate is not preserved, where the piers were embedded, among which were interposed. In the Theotokos of Chalcoprateia the chancel barrier would have been a rectilinear, low balustrade. In the small Topkapı basilica it has been proposed that the sanctuary occupied a single area all along the width of the basilica, attached to the eastern side of the church, but there is not enough evidence for this; even if this assumption is valid, there is no indication for any inner partition of the sanctuary. In general, a tripartite sanctuary is not supported by the existing facts for the Constantinopolitan basilicas of the 5th century.17
The inner part of the apse was filled with a , in front of which, and sometimes above the crypt, the Holy Altar was placed (Stoudios basilica, Theotokos of Chalcoprateia). The location of the ambo was central in the middle of the nave (Hagia Sophia, Topkapı basilica); in Topkapı basilica the solea is still preserved that connected the ambo with the sanctuary.
The tendency was towards anticlassicism. On the sculptured architectural members, especially on the capitals, is evident the trend for formalization and decorative character. On the Corinthian capitals from the pre-Justinianic Hagia Sophia, for example, the acanthus leaf becomes schematic and geometrical, showing an aesthetic turn towards abstraction. In respective members of the Stoudios basilica we ascertain the same phenomenon. In addition, the extensive use of drill creates sharp contrast between light and dark and abolishes plasticity. At the same time, however, certain elements of the classical heritage survive in the church architecture of the capital: the architraves of the colonnades of the Stoudios basilica remain rectilinear, with an entablature of classical formation. Likewise, the of the monumental porch of the pre-Justinianic Hagia Sophia marks the survival of a classical prototype, in spite of the general anti-classical tendency in the architectural sculpture.18
2. Justinianic architecture
From the second third of the 6th century, and mainly during the years of Justinian I (527-565), a Christian building program without precedent was developed, during which an important change is observed in the composition of ground-plans and in the way of roofing. The type of the timber-roofed basilica with galleries survived in the case of the church of Saints Peter and Paul (518/9); attached to the northern wall of the church was built the central-plan church of Saints Sergios and Bakchos, with a common atrium and a narthex; the church belonged to the palace of Ormisdas (residence of Justinian and Theodora before 527) to the southwest of the Hippodrome and near the shores of the Sea of Marmara. However, this type declined while a new type, that of the , was emerging, which was directly connected to the important changes on dome building and which marked the evolution of the Byzantine church architecture in relation to the form as well as to its symbolic meaning.
Except, however, the vaulting technique, effective changes are not observed on those elements (atrium, narthex, aisles and galleries) that could have attested changes in the liturgy and as a consequence in the arrangement of the spaces up to the point that this internal arrangement indeed corresponded to liturgical needs, as T.F. Mathews suggests. In the area of the presbytery only the chancel barrier became less transparent, with screens (vela) covering the spaces between the piers above the parapet slabs. This change announces the transformation of the chancel barrier to the temple screen of Byzantine architecture, when the sanctuary was clearly divided from the inner area of the church and an important part of the liturgy was out of sight of the faithful.19 After all, the formation of the space of the sanctuary did not present any changes in relation to the previous period. This can be attested on the central-plan church of Saint Euphemia: it is about a hexagonal edifice with an apse on every side erected in 429 as part of the palace of praepositus Antiochos. Around 608-626 this central-plan building was transformed to a church; from that period are still preserved remains of the synthronon, of the chancel barrier (in Π-shape) and of the solea in the area of the sanctuary.20
2.1. The new vaulting technique
The ground plan of the 6th century churches tend towards the square form, continuing the development of the 5th century. Internally, the arrangement of built piers served the creation of arches that could hold the spherical base of the , transferring the compressive thrusts upon the outer strong walls. In addition, the vaults were made of brick stones and hard mortar, making the constructions lighter. In the Justinianic Hagia Sophia, consecrated in 537, the masterpiece and turning point of the 6th century architecture in Constantinople, four solid built piers hold an equal number of arches. On the north and the south side they are simple arches; between the piers gallery colonnades are formed (with four free-standing columns at the ground floor and six at the galleries) carrying big drums pierced by arched windows. On the east and the west side the arches actually form exedrae covered by , which in their turn are widened at the bottom with a couple of two-storeysemicircular exedrae; these exedrae are supported by the central piers and by smaller ones near the eastern and western wall respectively. The semi-domes transfer part of the compressive thrusts of the dome upon these secondary piers. The dome rests on the four arches that connect the four central piers. Between the arches an equal number of are formed, which help in the transfer from the central square defined by the piers to the spherical base of the dome. The Justinianic dome (that collapsed already in 558) did not have a circular drum; the cupola rested directly upon the arches and on its base, between the ribs, arched windows were opened for the lighting of the church.21
A similar system of supporting the dome on four arches rested on an equal number of massive piers had been applied, according to R. M. Harrison, at the church of Saint Polyeuktos that was located on the Mese, between the Forum Bovis and the church of the Holy Apostles; remains of the church have been excavated in the quarter of Saraçhan.22 The church was erected by Juliana Anicia, descendant of the Theodosios dynasty and Justinian’s political rival, between 524 and 527. Through Hagia Sophia Justinian tried to surpass Anicia’s challenge, whose foundation constituted the most splendid until then edifice in the capital.23 Another forerunner of Hagia Sophia from the times of Justinian is the domed church of Saints Sergios and Bakchos (Küçük Aya Sofya Camii), built between 530 and 536. However, in the case of this church, which externally has an irregular square shape, the interior is formed into an octagon with the help of eight piers. The eight arches that connect these piers support a sixteen-sided dome; from the sides that correspond to the piers started thin transversal walls which connected the dome with the external walls of the square, transferring part of the compressive thrusts of the dome upon the external walls.24
What impresses more in the case of Hagia Sophia as well as in that of Saints Sergios and Bakchos, is that their architectural design was extremely ambitious in relation to the restrictions imposed by the lack of experience from similar constructions. Besides, the rich theoretical training of Anthemios is known, who along with Isidore of Miletos designed Hagia Sophia.25 The deficiency in the execution of the architectural design of the church of Saints Sergios and Bakchos, visible in the irregular ground plan of the edifice, as well as the collapse of many architectural elements within a short period of time, such as the original dome of Hagia Sophia, imply that the ambitious new architectural plans did not exactly correspond to the building experience of that period.26 Besides, the application of such daring architectural solutions did not continue beyond the middle of the 6th century. Soon enough the architects turned to simpler architectural compositions that were easier in constructing and did not entail many static problems.
One of the most important monuments of the age of Justinian in Constantinople is the church of the Holy Apostles (550), entirely destroyed today27 and known from descriptions in the sources (Procopios, Constantine Rhodios, Nicholas Messarites) and from monuments believed to have copied its pllan (Saint John Theologos in Ephesus and Saint Mark in Venice). The church was built above the Constantinian one and followed its ground plan of a free cross. Earlier it was believed that each arm was a three-aisled basilica with galleries and a dome; a fifth dome, higher than the other four, covered the area above the junction of the arms. Recent excavations of Ken Dark in the area of Fatih Camii brought to light new evidence. Based on these, Dark suggests the ground plan of a wide basilica with a transverse nave that projects beyond the side walls, giving to the monument a cross-shaped ground plan. A cross-shaped mausoleum for Justinian was erected on the northeast corner.28
2.2. The simplification of the architectural design
The simplification of the architectural design of Hagia Sophia appears already in the church of Hagia Eirene, the erection of which started right after the destruction of the Constantinian church by fire during the Nika Riot in 532. The Justinianic Hagia Eirene, which partly collapsed after an earthquake in 740 and only its lower part is still preserved, was a simpler domed basilica, three-aisled, with galleries, a narthex and an atrium. The central nave was covered to the east and the west of the dome with vaults, whereas to the north and south of the dome there were shallow arches with drums pierced with windows, so that the central core of the three-aisled basilica had the form of a cross.
2.3. Morphological elements and symbolical meaning
As far as the architectural type is concerned, Justinianic architecture marked the combination of the basilica with a central-plan building, a combination that reached its climax in a unique way in Hagia Sophia: a three-aisled basilica where the two-storey side aisles of quite limited proportions created, along with the narthex, an that surrounded the central, domed core, arranged in the shape of a cross. Although the domed cross-shaped core was not unknown in the church architecture of the Aegean,29 the Justinianic domed basilicas of Constantinople constitute the beginnings of the Byzantine conception of the Christian church as bearer of a high religious meaning. From that point, the unity of the area and the subjection of the separate parts to the dominant central dome corresponded to the perception, according to which the church was a microcosm with the dome symbolizing the heaven where dominates the one and only God.30 In this new form are interwoven in an original way and to a point that until then has never been accomplished elements of Roman ideology with Byzantine religious expression, since Justinian’s role in the design and the erection of Hagia Sophia is certain.31
The anti-classical tendency culminated during this period, a fact particularly visible in the stylistic technique of the capitals and the imposts of Saint Polyeuktos and of Hagia Sophia, where the emphasis is given to a decorative character unrelated to the organic origin of the decorative elements. The use of spolia columns and capitals did not hinder the creation of a harmonic impression of the whole, in which the separate elements of the composition are aiming at contributing in an indirect way. The multi-colored wall revetments, the mosaics and the ample light from plenty of windows create the impression that the inner spaces are confused and the volume of the supporting elements is disintegrated. In contrast to all this interest for the internal of the church, main bearer of the religious meaning, the external facades remain severe and plain, with no particular effort made to disguise their volume.32
1. However, the important differences between the Roman and the Christian basilica, with the more obvious one being that of the change of the arrangement from transversal to longitudinal and the maintenance of only one of the two apses that existed in the Roman basilicas, show that the tendency in the Christian edifice was towards a new form serving its particular purposes. See Johnson, M. J., «Architecture of the Empire» στο N. Lenski (ed.) The Cambridge Companion to the Age of Constantine (New York 2006), p. 283-5; Kinney, D., «The Church Basilica» Acta ad archaeologiam et atrium historiam pertinenta 15 (2001), pp. 115-35; Γκιολές, Ν., Παλαιοχριστιανική τέχνη: Ναοδομία (200-600) (Athens 1998), pp. 34-5; Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 51-55.
2. Mathews, T. F.,The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 119-25.
3. Mango, C., Byzantine Architecture (London 1986), pp. 42-3.
4. For the alleged Constantinian foundations in Constantinople see Dagron, G., Η γέννηση μιας πρωτεύουσας. Η Κωνσταντινούπολη και οι θεσμοί της (330-451), (transl. Μ. Λουκάκη, Athens 2000), pp. 446-466, with detail reference and critique to the sources; Mango, C., Le développement urbain de Constantinople (IVe-VIIe siècle) (Paris 1985), pp. 27, 35-6.
5. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική (Athens 1996, transl. Φανή Μαλλούχου-Τούφανο), pp. 89, 563, note 27. The hypothesis that the erection of the original church of Hagia Sophia started under Constantine the Great in 336 [see Krautheimer, R., «The Constantinian Basilica» Dumbarton Oaks Papers 21 (1967), p. 133 and note 61] is probably not correct. See Dagron, G., Η γέννηση μιας πρωτεύουσας. Η Κωνσταντινούπολη και οι θεσμοί της (330-451), trans. Μ. Λουκάκη (Athens 2000) p. 454.
6. During the riot that broke out after the condemnation of the archbishop John Chrysostom to exile by the empress Eudoxia.
7. Speck, P., «Konstantins Mausoleum: Zur Geschichte der Apostelkirche in Konstantinopel» in P. Speck (ed.) Varia VII: Poikila Byzantina 18 (Bonn 2000), pp. 113-66. Cf. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996) p. 89; Johnson, Μ. J.,«Architecture of the Empire» in N. Lenski (ed.) The Cambridge companion to the Age of Constantine (New York 2006), p. 294. For a summary of the sources in relation to the monument see Dagron, G., Η γέννηση μιας πρωτεύουσας. Η Κωνσταντινούπολη και οι θεσμοί της (330-451), pp. 457-464, who, based on the sources, dates the consecration of the church in 370, under Valens. The main source for the monument is Life of Constantine by Eusebios, IV.58-60.
8. According to Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), p. 89, there was one, not two edifices:, a central-plan church of the cross-shaped type erected under Constantine the Great. At the contrary, Downey, G., «The Builder of the Original Church of the Apostles of Constantinople. A Contribution to the Critisism of the Vita Constantini attributed to Eusebius» Dumbarton Oaks Papers 6 (1951), pp. 53-80, dates the monument to the years of Constantius II. Mango, C., «Constantine’s mausoleum and the translation of relics» Byzantinische Zeitschrift 83 (1990), pp. 52-58, believes there were two buildings and that Eusebios, who describes a central-plan building, refers to the mausoleum of Constantine the Great, whereas the church was erected later, during Constantius II.
9. Notitia Urbis Constantinopolitanae in Seeck, O., (ed.) Notitia dignitatum (Berlin 1876, repr. 1962), pp. 231-7; Mango, C., Byzantine Architecture (London 1986), p. 28.
10. The dating in 463 is widely accepted, but Mango maintains that the church was built earlier, before 454, and was transformed to the katholikon of the monastery around 460. See Mango, C., «The Date of the Studios Basilica» Byzantine and Modern Greek Studies 4 (1978), pp. 120-1. For the architecture of the monument see Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 19-28.
11. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 28-33.
12. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 33-9.
13. Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 129-42; Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 11-18, where the earlier dating is maintained for those parts of the pre-Justinianic church that have been excavated. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 133-4, believes that the porch is part of the Theodosian repairs. For the excavations in Hagia Sophia see Schneider, Α. Μ., Die Grabung im Westhof der Sophienkirche. Istanbuler Forschungen XII (Berlin 1941).
14. Γκιολές, Ν., Παλαιοχριστιανική τέχνη: Ναοδομία (200-600) (Athens 1998), p. 43.
15. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), p. 38.
16. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 16-17, fig. 2.
17. For an interpretation of all this evidence according to the Early Byzantine liturgical ritual, see Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 105-125, where the abundance of openings on the churches of the capital during this period, even on the east side, is commented as suggestive of massive participation in the liturgy, whereas the galleries are interpreted as the area of the catechumens; hence the direct access to the galleries is from the exterior of the church. As far as the aisles are concerned, it is not quite clear what purpose exactly did they serve. Cf. Also Mango, C., Byzantine Architecture (London 1986), pp. 42-3. Generally for the characteristics of the pre-Justinianic church architecture in Constantinople see also Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 143-4.
18. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 133-5.
19. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), pp. 105-10, 119-25, 179.
20. Mathews, T. F., The early churches of Constantinople. Architecture and liturgy (University Park, Pa 1971), p. 61.
21. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 258-64; Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 185-218; Taylor, R.,«A Literary and Structural Analysis of the First Dome of Justinian’s Hagia Sophia, Constantinople» Journal of the Society of Architectural Historians 55 (1996), pp. 66-78; Buchwald, H.,«St. Sophia. Turning point in the development of Byzantine Architecture?» in V. Hoffman (ed.) Die Hagia Sophia in Istanbul (Bern 1997), pp. 29-48.
22. Harrison, R.M.,«The church of St. Polyeuctos», in R.M. Harrison – N. Firatli (eds.), Excavations at Saraçhane in Istanbul, I (Princeton 1986), pp. 405-420; Harrison, R.M., A temple for Byzantium. The discovery and excavation of Anicia Juliana’s palace-church in Istanbul (London 1989). As far as the existence of a dome is concerned, however, there are some doubts. See Buchwald, H.,«St. Sophia. Turning point in the development of Byzantine Architecture?» in V. Hoffman (ed.) Die Hagia Sophia in Istanbul (Bern 1997), p. 43, but also Harrison, R.M.,«The church of St. Polyeuctos», p. 406.
23. See Harrison, R.M., A temple for Byzantium. The discovery and excavation of Anicia Juliana’s palace-church in Istanbul (London 1989), pp. 36-41; Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 147–148.
24. Alchermes, J. D., «Art and Architecture in the Age of Justinian» in M. Maas (ed.) The Cambridge Companion to the Age of Justinian (New York 2005), pp. 361-2; Svenshon, Η., Stichel, R.H.W., «Neue Beobachtungen an der ehemaligen Kirche der Heiligen Sergios und Bakchos (Küçük Ayasofya Camisi) in Istanbul», Istanbuler Mitteilungen 50 (2000), pp. 389-409. In reference to the possibility of a church being erected on the site of a martyrium (hence maybe the central-plan shape) see Bardill, J., «The Church of Sts Sergius and Bacchus in Constantinople and the Monophysite refugees» Dumbarton Oaks Papers 54 (2000), pp. 1-11, where it is supported anew, although with some alterations, the opinion of Mango in relation to the use of the church by a Monophysitic community under the auspices of Theodora.
25. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), p. 255-56; Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), p. 157.
26. Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 85-91, 213-217.
27. It was finally destroyed in 1469 in order for Fatih Camii to be erected in its place.
28. Dark, K. - Özgümüș, F. «New evidence for the Byzantine church of the Holy Apostles from Fatih Camii, Istanbul», Oxford Journal of Archaeology 21.4 (2002), pp. 393-413; Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 299-301.
29. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), p. 297.
30. Μπούρας, Χ., Ιστορία της Αρχιτεκτονικής, 2. Αρχιτεκτονική στο Βυζάντιο, το Ισλάμ και τη Δυτική Ευρώπη κατά το Μεσαίωνα (Athens 1994), pp. 32, 108-9; Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), p. 271. Cf. McVey, K., «The Domed Church as Microcosm. Literary Roots of An Architectural Symbol» Dumbarton Oaks Papers 37 (1983), pp. 91, 118-9.
31. Alchermes, J. D., «Art and Architecture in the Age of Justinian» in M. Maas (ed.) The Cambridge Companion to the Age of Justinian (New York 2005), p. 343; Mainstone, R.J., Hagia Sophia. Architecture, Structure and Liturgy of Justinian’s Great Church (London 1988), pp. 151-54; Buchwald, H., «St. Sophia. Turning point in the development of Byzantine Architecture?» in V. Hoffman (ed.) Die Hagia Sophia in Istanbul (Bern 1997), pp. 37-46.
32. Μπούρας, Χ., Ιστορία της Αρχιτεκτονικής, 2. Αρχιτεκτονική στο Βυζάντιο, το Ισλάμ και τη Δυτική Ευρώπη κατά το Μεσαίωνα (Athens 1994), pp. 31-3, 109, 120-1. Cf. Krautheimer, R., Παλαιοχριστιανική και Βυζαντινή αρχιτεκτονική, transl. Φανή Μαλλούχου-Τούφανο (Athens 1996), pp. 264-5.