OPPIDO MAMERTINA, DIOCESE OF. - Diocese and city in the province of Reggio Calabria, situated in a recessed position on the north-western slopes of the Aspromonte; close to the sea, among olive groves of considerable extent, it stands at some distance from the ancient Oppido, which was entirely destroyed by the earthquake of 1783.
Over an area of 216 sq. km., it has 42,000 inhabitants, all Catholic, distributed in 20 parishes served by 47 secular priests (Ann. Pont., 1957, p. 297). The diocese is a suffragan of Reggio Calabria.
For centuries there has been debate as to whether it is the successor of the ancient Matremium, as many local historians claim, or whether it should be identified with Matritano, on the slopes of the Sila, in the Savuto valley, formerly called Sabatum.
There is no foundation for the claim that Oppido was a bishop’s see from the earliest centuries of the Church, making it an heir of Metauria or Myria. In reality, no record of the diocese of Oppido exists before the arrival of the Normans in Calabria; and since no traces of it are found in either Greek or Latin sources prior to that period, it is debated whether it is of Byzantine or Norman origin. Since Oppido was originally Greek and remained faithful to the Greek rite until 1472, its foundation might be attributed to the Byzantines, who in Magna Graecia multiplied dioceses with excessive ease, or it might be thought that the Normans, having occupied the more important bishoprics of Calabria, found it necessary to establish the two small and insignificant dioceses of Oppido and Bova in order to placate the very numerous and turbulent Greek elements in the area. Perhaps Oppido can be identified with that Seraphinus seu Eternitinus, episcopus, who in the Lateran Council of 1179 appears alongside his metropolitan of Reggio. In a Greek document of 1188, published by Trincheria, there also appears, though unnamed, a piissimus episcopus Opidii, and his anonymous successors include one who paid the tithe in 1282, as recorded in the Vatican Regesta, and another who in 1301 received an assignment of 8 gold tari from Charles II of Anjou for translating medical books from Greek. The latter might be the Stefano mentioned in the same Neapolitan Registers of 1295 and in the Annales Casinenses of 1299. He would thus be the first bishop of Oppido whose name is authentically recorded.
It is worth noting that one of its bishops, named Basil, together with his colleagues from Bova and Gerace, in 1334 thwarted an attempt by the papal legate to suppress the Greek rite in these dioceses. It was instead an authentic Greek, Athanasius Calceopilo, a native of Constantinople and former abbot of the Patrìon, bishop of Gerace and later also of Oppido, who abolished the Greek rite and language in 1472. From that year Oppido remained united to Gerace until 1536, when it regained its autonomy under Paul III. During this period the two dioceses were almost always governed by cardinals “in commendam,” such as Bandinello Sauli, Francesco Armellino-Medici, and Alessandro Cesarini. Among other notable bishops are Teofilo Galluppi of Tropea; Sigismondo Mangieruva, who held a synod; Antonio Casonio; Giuseppe Perriuzzi of Paola, of the Order of Minims, a prolific writer on history and asceticism, who governed the diocese from 1714 to 1734, held a synod, and sought to reform ecclesiastical discipline; Ferdinando Mandarani; and finally Alessandro Tommasini of Reggio Calabria, who was the first bishop of the new Oppido and in 1818 went on to govern the metropolitan see of Reggio.