1. Early Ottoman period

The diocese of Nicaea, which existed since the early Byzantine period already, was maintained also during the whole Ottoman period with –apparently- a regular series of succession of metropolitans and without great gaps in the filling of the position of the diocese’s prelate. The special interest presented by the history of the diocese during the early Ottoman period is focused on the survival of the diocese itself.

As early as the Byzantine period, the diocese of Nicaea had a rather limited area of jurisdiction, due to the great density of the higher ecclesiastic authorities which were to be found in the area of Bithynia.¹ Given this fact, the great ware the Greek and generally the Christian element of the city and her area suffered during the Ottoman conquest (1331) and the long state of seize which had preceded it, contributed to leaving the diocese with a numerically scarce flock. From the beginning, one of the depletion factors of the Christian element was the islamization, in relation to which the area of Nicaea presents the interesting element of the early documentation of the parallel phenomenon of crypto Christianity; this is attested from the known circular of the patriarch Ioannes XIV Kalekas with which a “redemption” is given to the Christians of the Nicaea region which were forced by the “infidel tyrant” to leave the outer characteristics of their religious faith.² It is natural to consider that any Crypto Christians which remained for a certain time period in the area had no relation, typical or actual, with the local ecclesiastic authorities. We must also think of them as a lost flock for the diocese. Above any presence of a Crypto Christian element, Nicaea and the other settlements of the surrounding area maintain a Christian population, whose numerical power is very limited, as it becomes apparent by the Ottoman tax registers of the 15th and 16th century. It is characteristic that in a partial census of Nicaea itself in a register of the year 1454/55 only seven Christian households are documented.³

2. The establishment of the “gerontismos” authority

The general demographic weakness characterizes the Christian element of Bithynia as a total during the first ages of the Ottoman rule; nevertheless, the Ecumenical Patriarchate maintained active all the dioceses of the area which existed since the last period of the Byzantine rule, regardless of their extremely low demographical (and as a consequence also financial) base. Thus, and in a relatively limited area the dioceses of Chalkedon, Nicomedia, Nicaea and Prousa were maintained active, with only the last one having some slightly better financial possibilities thanks to the important financial role of the city and to the occupation of the Orthodox inhabitants with merchant and industrial activities. This policy of the Patriarchate to maintain all these metropolises was apparently caused by their proximity with Constantinople, and subsequently by the ability of these metropolitans to practice directly and constantly their sacerdotal duties in their province and in the same time to be present in Constantinople, even by living there permanently, and to participate in the Holy Council of the Patriarchate.

The situation was stabilized in the middle of the 18th century with the establishment of the authority of the “gerontism”, when the council of the so-called “gerontes” (elders) metropolitans became an institution and explicitly assumed control duties over the patriarchal acts and offered advice concerning the election of each patriarch. The “gerontes” were none other than the metropolitans of the provinces of Bithynia (Nicaea included too) and of Eastern Thrace, which were close to Constantinople; for many years they lived in the capital permanently and participated in the Holy Synod constantly.⁴

It appears then that during the early Ottoman period the diocese of Nicaea remained active due to its proximity with Constantinople, notwithstanding its weak population basis, which might not have been enough to cover the peşkeş tax which had to be paid to the Ottoman authorities with the appointment of each metropolitan, a tax which then might have weighted the patriarchal treasury in total. Furthermore, it is possible that symbolic reasons played a role in the survival of the diocese of Nicaea, since this city had housed two of the Ecumenical Councils, the First (325) and the Seventh (787), and had also been the seat of the Ecumenical Patriarchate during the years of the Latin rule in Constantinople (1204-1261).

3. The transfer of the metropolitan seat to Kios

The survival of the diocese was not followed by the survival of its seat in Nicaea itself, since the former had substantially decayed after the Turkish conquest and had become a minor settlement with an extremely limited population and financial power. A result of the abovementioned development was the transfer of the seat of the diocese to Kios (Gemlik), former harbour of Nicaea which apparently had a substantial Christian population and, as a harbour, presented better financial and developmental perspectives, as the later evolution of the city indicates. The transfer of the seat to Kios is attested for the first time in the Episcopal catalogues of d’ Anville (1725), but is must have taken place earlier.⁵ Obviously the renovation and the re-founding of the old church of the Assumption of the Holy Mother (the so-called Pazariotissa) in 1692 must be related with the settling of the metropolitan of Nicaea in Kios.⁶ The church is known to have operated until the end as the city’s cathedral.

It is unknown exactly when the seat of the metropolitan of Nicaea moved to Kios, but this might have happened already from the end of the 14th or the beginning of the 15th century, when the previous ecclesiastic authority (archbishopric) of Kios became inactive and the area of its jurisdiction passed under the control of Nicaea, as shown by Nicaea’s interventions in the local monastery of the Holy Mother Romaniotissa since 1395.⁷ In this issue the patriarchal berat from 1483 and 1525 are not particularly illuminative, since they mention Nicaea (Iznik) itself as the seat of the metropolitan, whereas in the berat of 1662 the city is not mentioned at all.⁸ Nevertheless, the mention of Nicaea itself as the seta of a metropolis has passed in the later berat, of the years 1754, 1757, 1835, 1860 and 1884,⁹ which means that during the compilation of the specific texts the transfer of the seat of the metropolis from Nicaea to Kios was not taken into account, an omission which probably was due to the proximity of the two cities.

4. Late Ottoman period

During the recent period of the late Ottoman era, the demographic and financial development of the Greek and of the Christian element in general acts positively also in the ecclesiastic province of Nicaea, whose area of jurisdiction is increased and, until the beginning of the 20th century, it extends over 26 Orthodox communities, mostly of Greek-speaking but also of Armenian and Turkish-speaking population. The most important of these communities is the capital of the province Kios, a city of 10,000 inhabitants, Greeks in their majority, also the Armenian-speaking community of Ortaköy and those of Lauka, Kouvouklia, Armoutles and Furlacim. The total number of the flock of the province just before the outbreak of World War I is 33,470 people (based on the sources of the Ecumenical Patriarchate, which however should be not be accepted without reserve).¹⁰