San Giovanni I di Napoli

Saint John I of Naples, known in Italian as San Giovanni I di Napoli, was bishop of Naples in Campania during the first half of the fifth century. He is venerated as a saint in the Catholic Church. Virtually nothing can be established about his birth, family, or early life; no contemporary vita survives, and later notices are short. The principal documentary basis for his career is the medieval Catalogus episcoporum Neapolitanorum, an episcopal list that records the duration of each bishop's tenure and the day of burial. According to that catalogue, John occupied the see for eighteen years, ten months, and twenty-five days, and his depositio was observed on 3 April. Combining the lengths of successive episcopates, historians have conventionally placed his government of the diocese from about 414 until 432. He is listed as successor to Saint Severus, an earlier bishop of Naples whose own cult is better attested.

John's years as bishop coincided with a turbulent era in the Western Roman Empire, as imperial authority in Italy weakened and Campania remained a densely Christianized region with an already developed local calendar of martyrs and confessors. Naples was an important Tyrrhenian port, and its church looked to Rome while cultivating its own saints, among them Aspren, Agrippinus, and Severus. The act for which John I is remembered in liturgy and local tradition is the translation of the relics of Saint Januarius, the martyr who became the principal patron of Naples. Neapolitan tradition holds that John had Januarius's remains brought from the Agro Marciano in the territory of Puteoli (modern Pozzuoli), the place associated with the saint's beheading, into an extra-urban cemetery of Naples. That cemetery later developed into the Catacombs of San Gennaro. The translation is traditionally dated to about 431, near the end of John's episcopate, and it is this deed that the Roman Martyrology cites when it commemorates him.

Independent fifth-century evidence for other aspects of John's pastoral work is lacking. Later medieval and early modern writers sometimes attributed church foundations or clerical organization in Naples to the early bishops as a group, but specific buildings or decrees cannot be assigned to John I with security. He must be distinguished from later homonymous bishops of the same see, including John II and the seventh-century John IV of Naples, who is likewise honored as a saint, and from Pope John I, who died in 526. The Catalogus remains the main source for the length of his episcopate and for the calendar date of his burial; liturgical books then preserved his memory in connection with Januarius.

John I died in Naples, according to the received chronology, in 432. The Roman Martyrology commemorates him on 3 April as the bishop of Naples who transferred the body of the martyr Januarius from the district of Puteoli into the city. His cult belongs to the ancient, pre-congregation layer of sanctity: he was not canonized by a formal papal process of the later Middle Ages or the modern period. He is counted among the holy bishops of the Neapolitan church, but he did not acquire a large independent set of patronages of places, trades, or causes. Because almost all that is known of him derives from the episcopal catalogue and from the tradition of the Januarius translation, any fuller biography would be conjectural. He remains, for historians, an important but sparsely documented figure in the fifth-century history of the church of Naples.