Probably third century, authentic Roman martyr. Since no certain acts of her martyrdom exist, it is impossible to determine the date of her death and the persecution in which she perished. The opinion that she died of a natural death, as stated in the Roman martyrology, stems from the apocryphal Passion of Nereus and Achilleus. Certain Gnostic writings quite probably led to the erroneous identification of the saint with the daughter of St. peter the apostle. Petronilla's tomb, as marked in an itineraria of the seventh century, was located in the cemetery of St. Domitilla on the Via Ardeantina. A fresco of the fourth century depicts a holy woman entering heaven and bears the inscription "Petronilla martyr." During the pontificate of Pope siricius (384–399), a basilica was erected over the saint's tomb. Though G. B. de Rossi contested the allegation that Petronilla was a martyr, the opinion that she died for the faith has prevailed. In art Petronilla is represented as a little girl holding a palm and a book in her hand. She is a special patroness of France.
Feast: May 31.
Bibliography: a. butler, The Lives of the Saints, rev. ed. h. thurston and d. attwater, 4 v. (New York 1956) 2:434. r. dall'ara, Petronilla e le altre: il mestolo dalla parte di lei (Mantua 1998).