ISCHIA, DIOCESE of. — Founded in the 12th century on the largest of the islands in the Gulf of Naples; area 46.3 sq km; entirely Catholic population of 53,000 inhabitants; municipalities 6. The diocese, a suffragan of Naples, comprises only Ischia; 18 parishes, 3 male and 12 female religious communities, an archaeological museum, and a library with 13,000 volumes.
The island is variously named by Greek and Latin poets and historians. The present name began to appear around the 8th century. Its geological formation is of volcanic origin, probably dating from the period known as the Diluvian period. Its first inhabitants are traced back to the 3rd millennium B.C.; subsequently the Etruscans, Phoenicians, Syracusans, Hellenes, and Latins landed there and established colonies. As early as 192 B.C.
the Romans, because of its extraordinary and abundant thermal waters, which are still exploited today, built several baths there, as is proved by inscriptions, bas-reliefs, and statues unearthed in recent years. According to the Passio, the body of the African martyr St. Restituta was said to have been deposited on the shore of the island, and she was buried at Lacco Ameno. In the spring of 1950, when the pavement of the church of S. Restituta was removed, other, more ancient pavements superimposed upon it were found, and at a depth of 1.35 m below the floor level several tombs and a Christian clay lamp were discovered; it was also established that the apsidal wall dates from the Roman period.
The history of the island is not unrelated to all the events that followed the fall of the Roman Empire through the entire Middle Ages. It was destroyed by numerous earthquakes and eruptions of Mount Epomeo, plundered by pirates, and disputed by various invaders. The Castle, which rises on a large rock connected to the island by a bridge, was built in 474 B.C. by Hiero of Syracuse and rebuilt in 1441 by Alfonso V of Aragon; for centuries it was the island’s stronghold and the refuge of survivors who had escaped earthquakes and the raids of pirates.
I. is the birthplace of St. Giovanni Giuseppe della Croce (1654–1734) and Baldassarre Cossa (1367–1419), antipope under the name of Giovanni XXIII. The Cathedral is dedicated to Maria S.ma Assunta in Cielo. — Vedi tav. XVII.