The exact time of Ioannina's foundation is unknown. It is commonly identified with an unnamed new, "well-fortified" city, recorded by the historian
Procopius (
De Aedificiis, IV.1.39–42) as having been built by the
Byzantine emperor
Justinian I () for the inhabitants of ancient
Euroia, but archaeological evidence for this is lacking; indeed, early 21st-century excavations have brought to light fortifications dating to the
Hellenistic period (4th–3rd centuries BC), the course of which was largely followed by the later
Castle of Ioannina. The name Ioannina appears for the first time in 879, in the acts of the
Fourth Council of Constantinople, which refer to one Zacharias, Bishop of Ioannine, a
suffragan of
Naupaktos. After the
Byzantine conquest of Bulgaria, in 1020 Emperor
Basil II () subordinated the local bishopric to the
Archbishopric of Ohrid. In the
treaty of partition of the Byzantine lands after the
Fourth Crusade, Ioannina was promised to the Venetians, but in the event, it became part of the new
principality of Epirus, founded by
Michael I Komnenos Doukas. Following the assassination of the last native ruler,
Thomas I Komnenos Doukas by his nephew,
Nicholas Orsini, in 1318, the city refused to accept the latter and turned to the Byzantines for assistance. On this occasion, Emperor
Andronikos II Palaiologos () elevated the city to a
metropolitan bishopric, and in 1319 Andronikos II issued a chrysobull conceding wide-ranging autonomy and various privileges and exemptions on its inhabitants. The new metropolis was placed in 53rd place among the metropolitan sees subject to the
Patriarchate of Constantinople, but rose to 42nd place under
Andronikos III Palaiologos (), and further to 33rd place in . The suffragan sees of the new metropolis in the 14th century are not known, but are likely the same four sees as those attested for : the bishoprics of
Vela,
Dryinoupolis,
Bouthrotos/
Glyky, and
Himarra. Under the regime of
Thomas II Preljubović (1367–1384), the citizens and the local Church suffered greatly: Thomas confiscated property in favour of his Serb followers, and drove the Metropolitan Sebastianos to exile; nevertheless, he was able to repel successive attempts by the Albanian chieftains
Peter Losha and
John Bua Spata to capture the city, most notably the great surprise attack of 1379, whose failure the Ioannites attributed to intervention by their patron, Saint Michael. After Thomas' murder in December 1384, the citizens of Ioannina offered their city to
Esau de' Buondelmonti. Esau took care to recall those exiled under Thomas, including the Metropolitan Gabriel, and restore the properties confiscated by him. Esau secured a period of peace for the city, which lasted until his death in 1411. The Ioannites then invited the
Count palatine of Cephalonia and Zakynthos,
Carlo I Tocco, as their new ruler. Following the death of Carlo I in 1429, in October 1430 Ioannina surrendered to an Ottoman army. Led by the Metropolitan, the notables of the city secured a charter, the "Order of Sinan Pasha" (ὁρισμὸς τοῦ Σινᾶν πασᾶ), which outlined the privileges of the city: the church bells would continue to be tolled, no mosques were to be erected, and the authority of the Metropolitan and the possessions of the Church were to be respected. This privileged position lasted until 1611, when the city was engulfed by the peasant revolt led by
Dionysius the Philosopher, the
Metropolitan of Larissa. In its aftermath, Christians were evicted from the
Ioannina Castle, and Muslim and Jewish families settled in their stead. The residence of the Metropolitan was moved from the Castle to the
Church of St. Athanasios, where it remains to this day (the church was rebuilt in 1832 after it was gutted in a fire in 1820). The original
cathedral of the city, which lay in the southeastern part of the Castle, survived at least until 1430, but is recorded as being ruined by 1596/97. Columns from it were reused in the
Fethiye Mosque, built by
Ali Pasha in 1795. A separate bishopric for the region
Zagori was established from the Metropolitan's jurisdiction in the late 16th century, but it was disestablished soon after. Its seat was probably the
Rongovou Monastery. In 1659, Sultan
Ahmed III established the
Exarchate of Metsovo as a special privilege for the villages of the region of
Metsovo. The exarchate was under the direct jurisdiction of the Patriarch of Constantinople, and lasted until 1795. Following the
Asia Minor Disaster and the
Greco-Turkish population exchange, in 1924 a separate Metropolis of Metsovo was established for the provisional settlement of bishops evicted from Asia Minor. Its first and only metropolitan was the former Metropolitan of Ganos and Chora, Timotheos (1924–1928). ==Bishops==