Roman Catholic Diocese of Mariana in Corsica

The Diocese of Mariana in Corsica (Latin: Dioecesis Marianensis) was a Roman Catholic ecclesiastical territory in Mariana, Corsica, in the north-eastern corner of the island. In 1563 the diocese was united with the Diocese of Acci(a) to form the Diocese of Accia and Mariana. Both dioceses were poor and had lost population. Mariana had been abandoned and its bishop lived in Bastia to the north, the seat of the civil government of the island. The Cathedral sat alone near the banks of the River Golo some three miles from the sea, in the midst of fields.

In the earliest history of the diocese, Ferdinando Ughelli reports the existence of a Saint Petreius, Bishop of Mariana and martyr, for whom a shrine was built by a certain Ugo Colonna of Rome, according to the Sacra Corsicae Chronica of Salvatore Vitale. Giuseppe Cappelletti points out that Vitale is the only source of the story, but that Ugo Colonna built the Cathedral, which was dedicated to the Assumption of the Virgin Mary, and that San Petreio was a different church. He also notes that the Martyrologies do not report the existence of a bishop, a bishop and martyr, or just a martyr named Perseo or Petreio. Pius Gams both italicizes the name Perseus and puts it in parenthesis, indicating grave suspicion.

Ughelli then reports the existence of a Bishop Catanus, Corsicanus episcopus, who attended the Synod of Arles in 314. Neither the name nor the diocese of Mariana occurs, however, in the list of those who attended the Synod.

Ughelli thirdly reports the existence of Bishop Leo of Corsica, on the authority of letters of Pope Gregory I and the Sacra Corsicae Chronica of Salvatore Vitale. Bishop Leo did exist, but Pope Gregory addresses him as episcopus in Corsica, bishop in Corsica, not bishop of Corsica. Leo had been sent by the Pope as an Apostolic Visitor, since, as the Pope notes, the dioceses of Corsica had long been vacant.

The fourteenth century was a period of extreme crisis in Corsica. Roger Caratini notes that the population of ordinary people on the island had decreased by 8% between 1300 and 1350, mostly by migration to the territory of Pisa; then came the Black Death; between 1350 and 1400 the population decreased another 19%. The ability to maintain traditional institutions in the face of the new Genoese overlords was greatly compromised.

In 1453 Pope Nicholas V entered into a verbal agreement with the Republic of Genoa, which specified that, although the Pope maintained the exclusive right to appoint bishops on the Island of Corsica, he would appoint only Genoese subjects who were acceptable to the Government. The Genoese government turned the island over to the administration of the Genoese Banco di S. Giorgio, under new statutes for Corsica were issued, the Capitula Corsorum, which specified that bishops on the island had to be natives of the island. In 1464, however, the Republic of Genoa came under the domination of the Duchy of Milan, and it was the Milanese who decided appointments. In 1479 the Milanese were compelled to evacuate Corsica, and their regulations were nullified.

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