MISENO. - An ancient diocese in Campania, from the Augustan age the station of the Roman fleet in the Tyrrhenian Sea.
The known bishops are Concordio (501-502); Pellegrino, remembered as legate of Pope Hormisdas to Constantinople in 517 (Lib. Pont., I, p. 269); Costanzo between 558 and 560 (Jaffé-Wattenbach, no. 981); Benenato in 592 to whom Gregory the Great also entrusted the church of Cuma, uniting it with M.; he was however later summoned to Rome and the diocese of M. was administered by Fortunatus, bishop of Naples.
The Martyrologium Hieronymianum lists on 23 September the deacon Sasso, martyr of the group of St. Januarius (v.), as a martyr of M.; he is also remembered on the same date in the Calendar of Carthage and in the Neapolitan stone calendar; in his honour Pope Symmachus (498-514) erected an altar in the oratory of St. Andrew in the Vatican (Lib. Pont., I, p. 216).