TREBISOND (TRAPEZUNTE, TRABZON). - The Greek bishopric of T., later elevated to a metropolitan see, already existed at the time of the Council of Nicaea (325).
Under Diocletian, St. Eugenius, the future patron saint of the city, died a martyr there. The development of Christian life was evident in the foundation of numerous monasteries and celebrated churches. The bishops of T. participated in the Councils of Constantinople. The bishopric followed the fate of Constantinople in the schism of the 11th century. After the establishment of the small Empire of T. by the Comneni in the 13th century, the city could no longer attain the power it had enjoyed as part of the Byzantine Empire. However, it cultivated relations with Western powers and with Venice, Genoa, and Florence, formalized through treaties, and sought support from the West, including the Pope, when its very existence was threatened by the Turks in the 15th century, who destroyed the Empire of T. in 1461 (v. ORANTE, IMPERO D’, II. *Impero latino d’Oriente*).
The Latin bishopric of T. was erected in 1314 but became titular by the 15th century. A Franciscan convent is attested from the year 1314; it still existed in 1390. A Dominican monastery is also known to have existed. Later, in 1652, the Capuchins attempted to exercise their apostolate from their mission in Georgia, but it was not until 1845 that the mission of T. could be established, including the nearby cities of Sinope and Samsun; the superior of the mission was granted the faculties of an apostolic prefect. Later, the Mechitarists and the Jesuits, under Leo XIII, came to the aid of these regions, as did the Sisters of St. Joseph and the Armenian Sisters. The tragic events that befell the Armenians in 1895 and during the First World War (1914-18), along with the forced emigration of Christians from the regions around the Black Sea, were disastrous for the apostolic prefecture of T., which became a simple mission after the decree of 12 September 1896 that abolished the "Prefectures of Apostolic Missions among the Eastern Churches." On 20 June 1931, a mission "sui iuris" was created in T. for Latin-rite faithful (AAS, 23 [1931], pp. 402-403), entrusted to the Capuchins.
The Catholic diocese of the Armenian rite (erected in 1850) was already vacant, impeded, and dispersed by 1932.
Among the illustrious figures of T., Cardinal Bessarion is remembered for writing an *Encomium* in honor of his native city, published by Spy. Lampros in the journal *Néos* (XVIII, 13 [1916], pp. 145-204). At the Council of Florence, the metropolitan Dorotheus subscribed to the bull of Union. In the first half of the 17th century, the metropolitan Cyril embraced union with the Catholic Church and was consequently expelled from his see (v. C. Giannelli, in *Orientalia Christ. Periodica*, 15 [1949], p. 167 ff). Papal letters addressed to the Emperors of T., still preserved, date from the years 1291, 1329, 1434, and 1460. The abbot of the Mechitarists of Venice, Ignatius Ghirurkean, a native of T., also rendered distinguished service to T. by founding a school there in 1876.