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St.Sergius & Bachus


Small St.Sofia Mosque – Ss. Sergius and Bacchus Church

Small St. Sofia Mosque is located between Cankurtaran and Kadırga quarters in Eminönü District, 20 km away from the southern seaside of Mediterranean ramparts. Although it is stated in some sources that there was a pavilion of Big Palace, which is known as Hormidas Palace, and a basically planned church established for Apostle Petrous and Pavlos near Small St. Sofia Mosque, there is no proof which determines their exact locations.

Small St. Sofia Mosque or St. Sergius and Bacchus church with its former name, which is the useable oldest structure of İstanbul today, was constructed between the years 527-536. According to the legends stated in the sources about the construction of the building (Millingen 1912), at the 1st Anastasyus Period, 1st Justiniaunus and his uncle 1st Justinos were condemned to death due to an allegation that they had a rebellion against the Emperor Anastasyus. One night before the execution, the Emperor Anastasyus sees the saints St. Sergius and Bacchus in his dream and the saints testifies in favour of 1st Justiniaunus and 1st Justinos. The emperor, who is affected by this dream, forgives them. When 1st Justiniaunus becomes emperor, he establishes St. Sergius and Bacchus church as a vow church in order to show his gratitude to these saints.

After the conquer of İstanbul, the building, which was used as a church for nearly 1000 years, was changed to a mosque by Hüseyin Agha, the Kapu Agha, in 1504 during the 2nd Bayezid period.

Architectural Description

The building is one of typical samples of central planned, first period Byzantine churches in the capital Constantinople. Narthex lies at the west and semi-hexagonal shaped apsis lies at the east side of the irregular, rectangular planned church. The octagonal planned centre area, which was placed in the irregular rectangle, was enlarged with semi-circle shaped niches called exedra. The location integrity has been ensured between the centre area and apsis by placing polygonal shaped pillars to the corners of this centre area and two each column among these pillars. In terms of plan, the building has the similar characteristics with Ravenna – St. Vitale, Aachen – Aix Le Chapella and Basra – Bacchus churches; but it is completely different in third dimension.

On the centre area, there is 16 sectioned dome carried by eight big pillars on its corners. Eight of these sections are plain and eight of them are concave. Arch shaped windows have been opened on the plain sections. The upper surface of the corridors providing passage from the centre area to rectangular form takes shape of a gallery at the upper floor. At the gallery floor, the upper surface of the exedras is furnished with semi – domes carried by three arches.

It is being supposed that the inner walls were ornamented with mosaics during construction, as seen in the buildings of the same period. But today there is no proof verifying this supposition; the inner surface of the building is fully plastered. The only ornament in the building belonging to Byzantine Period is an architrave formed with bunch of grapes and leaves having a slender workmanship at the gallery floor level, around the centre area. It is being asserted that the building was constructed on the area of a tempest made on behalf of Bakus, the God of wine, in idolatry period and the name Bacchus came accordingly.

Building Material

The building material used for St. Sergius and Bacchus church is stone, brick and plaster. Except the restored parts, the walls on northern, western and eastern fronts are made by reinforcement of bricks with stones arranged in wide intervals. The bricks of 70 x 35 x 5 cm are adhered together with plaster of 4 – 5 cm. On the southern front which is a 19th century structure there are irregular laid stones and bricks. Various lime types have been used for stone lines made for reinforcement of bricks. In the building, for the pillars, shelled limestone adhered with 4 cm plaster was used on the ground floor and brick was used on the gallery floor. Bricks were used as material for the vaults of the corridors and the gallery floor and for the central dome, and the bricks are laid in a manner to form radial pointing united at the centre of the vault.

The columns between the pillars are made of red and green serpatine, the head of columns and the architrave at the gallery floor level are made of Mediterranean marble. After the building was changed to a mosque, the pulpit muezzin gallery added to the building are also made of marble.

The Changes in the Building

According to the sources, the first damage and thus the first restoration in the building had been done after the Iconoclasm movements in the 9th century (Müller – Weiner 1977). And after the Latin invasion, the inner ornament needed to be restored (Paolesi 1961).

In 1054, Hüseyin Agha, the Kapu Agha, changed the building to a mosque and during this changing works all inner ornaments of the building were changed and some parts specific to a mosque were added to the building. These parts were a pulpit to south – east, a muezzin gallery to north – west in the inner side and a congregation area in front of the western wall in the outer side. Many windows at various dimensions were opened with ottoman architectural characteristics; and some of the existing windows were closed.

An independent minaret was established to the south – west corner of the building. The characteristic of the first minaret is not being known. It is being stated in the sources that a new minaret with Baroque style was made in the 18th century (S. Eyice 1978). The body of the Baroque style minaret was placed on an octagonal pulpit; the body climbs on the Baroque profile arches and joined to a minaret balcony with a bracelet part. The banister of the minaret balcony having baroque style ornaments was made of plain plates. The minaret having a lead coated classical spire was destroyed up to its pulpit in 1936 due to unknown reasons. The minaret, which remained ruined for a few years, was rebuilt in 1955.

Since 1600, 89 earthquakes with intensity bigger than 6, were observed in İstanbul, which is located on an important seismic zone. Thus, it is certain that Small St. Irene Mosque lived more earthquakes (N. Çamlıbel 1991). It was stated that in Hüseyin Agha’s foundations (the Kapu Agha), the plasters fell and the windows at north and south were broken in the earthquake of 1968 and most part of the building was damaged in the earthquake of 1763; and the restoration works of the building were given to Ahmet Agha (S. Eyice, 1978).

In 1870 – 1871, a railway was established in the region between the building and the northern sea ramparts in a manner to pass 5 km away from the building. The railway, which is at an altitude of 1 m. from the ground level, served as single line for nearly 50 years. According to the sources, as the stones of the southern walls fell at each pass of the train, a wall in the Ottoman style was laid in 1877 (Mathews 1971). At the beginning of the 20th century, the railway was made double lined by increasing 3 m from the ground level.

The building, which was used as a sheltering place during Balkan War by the people who escaped from the war, was restored twice in 1937 and 1955, in the Republic Period (S. Eyice, 1978). The front of the building, which was known to be plastered and whitewashed, was restored after 1955 and brick and stone lays were made to be visible at all fronts except the drum of cupola.

There are some cracks at north – east and south – east sides, especially at exedras of the building, which is today used as a mosque. These continuous cracks begin from the cupola, pass the gallery vaults and go up to the outer walls of the building. The necessary activities should be carried out in order to find the occurring reason of these cracks and to repair them.