Thera (Santorin), Diocese of (Santorino), in the Cyclades. About the year 2000 B.C., the extinguished volcano of the island renewed its activities, destroyed the population, and a portion of the island which was engulfed in the sea. In 236 B.C. another eruption separated the island of Theresa from Thera; in 196 B.C. the islet of Hiera sprang up (Palaeo-Kaimeni); in A.D. 46 appeared Thia, which was afterwards swallowed up by the sea; in 1570 a portion of the island of Thera caved in; in 1573 and 1711 two new islands arose; in 1866 there was a new volcanic eruption which lasted two years. The ancient town of Thera has been discovered at Haghios-Stephanos, near Mesavouno; the Ptolemies established an important garrison there. Some time after the eruption of the year 2000 B.C., the island called Calliste was repeopled by the Phoenicians, then by the Dorians who named it Thera about the year 620 B.C.; it became successively a tributary of Sparta, Athens, the Ptolemies, and finally the Romans. It is believed that Christianity was already introduced there in the second century and that certain tombs belonged to that epoch (Hiller von Gartringen, "Thera", III, 195); a very old church dedicated to Saint Michael and other very ancient churches have been found there. The See of Thera was a suffragan of Rhodes in the seventh and tenth centuries (Gelzer, "Ungedruckte . . . Texte der Notitiae episcopatuum", 542, 558). It became a metropolitan see in the eighteenth century and after the incorporation of the island with the Kingdom of Greece it was reduced in 1833 to a bishopric, which rank it still holds.

Le Quien (Oriens christ., I, 941) and Hiller von Gartringen (Thera, III, 198) give a list of twenty Greek bishops, of whom the greater part are posterior to the sixteenth century; this list could easily be completed. In 1207 the island fell into the power of a Latin lord, himself subject to the Duke of Naxos; the population decreased continually and in 1457 there were no more than 300 persons. In 1566 Thera fell under the domination of the Turks and took the name of Deir-Menlik. It received the name of Santorin only in the Middle Ages from Saint Irene to whom the island had a special devotion. A Latin diocese, suffragan of Naxos, was established there; a number of bishops are known, who belonged principally to the fourteenth century (Le Quien, op. cit.; III, 1007-12; Eubel, "Hierarchia catholica medii aevi", I, 456; II, 252; III, 309). Thera, in the district of the Cyclades, numbers 15,000 inhabitants, of whom 400 are Catholics; 8 secular priests; 1 parish; 2 churches with a resident priest; and 6 chapels. There is also a house of Lazarists, a convent belonging to the Sisters of Charity and another to the Dominican Sisters. The bishop has jurisdiction also over the islands of Ios, Amorgos, Siphnos, Seriphos, and Melos; the last only has Catholic inhabitants.

SMITH, Dict. of Gr. and Rom. Geog., S.V.; PEGUES, Histoire du volcan et des iles volcaniques de Santorin (Paris, 1842); CIGALLA, General statistics of the Island of Thera (Hermopolis, 1850), in Greek; LACROIX, Iles de la Grece (Paris, 1853), 484-92; MAMET, De insula Thera (Lille, 1874); FOUQUE, Santorin et ses eruptions (Paris, 1879); VON GARTRINGEN, Thera (3 vols., Berlin, 1899-1904); Missiones catholicae (Rome, 1907), 149.

S. VAILHÉ