ISCHIA, DIOCESE OF. Founded in the 12th century in the largest of the islands of the Gulf of Naples; area 46.3 km²; entirely Catholic population of 53,000 inhabitants; 6 communes. The diocese, suffragan of Naples, comprises the island alone; 18 parishes, 3 male religious communities, 12 female, an archaeological museum and a library with 13,000 volumes.
The island has been variously named by Greek and Latin poets and historians. Its present name begins to appear around the 8th century. Its geological formation is of volcanic origin, probably from the so-called diluvial period. Its first inhabitants are traced back to the 3rd millennium B.C.; subsequently the Etruscans, Phoenicians, Syracusans, Greeks and Latins landed and established colonies there. As early as 192 B.C.
The Romans, because of its prodigious and abundant thermal waters, 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 would have been deposited on the shore of the island, and she would have been buried at Lacco Ameno. In the spring of 1950, when the floor of the church of St. Restituta was renewed, older ones were found superimposed beneath it, and at a depth of 1.35 m from the floor some tombs and a Christian terracotta lamp were discovered; it was also ascertained that the apse wall is of Roman date.
The history of the island is not unrelated to all the events that followed the fall of the Roman Empire down to the entire Middle Ages. It was destroyed by numerous earthquakes and eruptions of Mount Epomeo, plundered by pirates and contested 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 stronghold of the island and the refuge of survivors fleeing earthquakes and pirate raids.
Ischia is the birthplace of St. John Joseph of the Cross (1654-1734) and of Baldassare Cossa (1367-1419), antipope under the name of John