ACERRA, DIOCESE of. — In the Campania region, in the province of Naples, suffragan of the latter. It occupies the territory situated between Naples and Caserta, with an area of 140 sq. km and a population of approximately 50,000 Catholics, 22,000 of whom are in the city and commune of A. The diocese contains 46 churches, 20 parishes, 48 diocesan priests, and 25 religious priests.
A., one of the oldest cities of Campania, already mentioned in 322 B.C. as civitas sine suffragio, was destroyed by Hannibal during the Second Punic War in 216. The Romans rebuilt it, and later, in the new administrative division made by Augustus, it was assigned to Region I (Latium and Campania). In the Middle Ages it formed part of the duchy of Naples, suffering the devastations of the Lombards. Erected as a county after the Norman conquest, it was often involved in the rebellions of its counts against the kings of Sicily. Before falling into the power of the Angevins at the end of the 13th century, it had been, from the first decades of that century, a fief of the counts of Aquino. It endured the siege of the Aragonese in 1420, and in 1480 it definitively surrendered to King Ferdinando I, who, at the beginning of the 16th century, ceded it as a fief to Ferdinando de Cardenas. A. remained in the possession of this family until 1806.
The origins of the diocese cannot be assigned, as Gams did, to the end of the 5th or the beginning of the 6th century, because Concordius, purportedly bishop of A. and present at the Roman Synod of 501 and 502, was instead bishop of Miseno. Moreover, there is no subsequent information about bishops of A. until the second half of the 11th century. It is therefore more probable that A. had its first bishops with the beginning of Norman rule. Among the most distinguished were Cardinal Vincenzo Carafa (1535), the Neapolitan nobleman Vincenzo Pagano (1606), and Ciro degli Altieri (1761), also from Naples. Monuments worthy of note are the Cathedral, dedicated to the Assumption and rebuilt in the 19th century, and the church of the Annunziata, with a 14th-century panel depicting the Annunciation.