Little is known of her life; the little information we have about her came from her private revelation to her devotees. Martyred at the age 14, she enjoyed fame 1800 years after her death.
In 1802 the remains of a young woman were found in the catacomb of St. Priscilla at the Via Salaria, Italy. It was covered by stones, the symbols on which indicated that the body was a martyr named St. Philomena. The vial containing dry blood (as it was custom to bury a sample of the blood of the martyrs) and the bones were exhumed, catalogued, and effectively forgotten since there was so little known about the person. (The sample of her blood made her the intercessors of those with blood related problems).
In 1805 Canon Francis de Lucia of Mugnano, Italy was in the Treasury of the Rare Collection of Christian Antiquity (Treasury of Relics) in the Vatican. When he reached the relics of St. Philomena he was suddenly struck with a spiritual joy, and requested that he be allowed to enshrine them in a chapel in Mugnano. After some disagreements, settled by the cure of Canon Francis following prayers to Philomena, he was allowed to transfer the relics to Mugnano. Miracles began to be reported at the shrine including cures of cancer and healing of wounds. Philomena became the only person recognized as a saint solely on the basis of miraculous intercession as nothing historical was known of her except her name and the evidence of her martyrdom.
Pope Leo XII granted permission for the erection of altars and churches in her honor. Pope Gregory XVI authorized her public veneration, and named her patroness of the Living Rosary. The cure of Pope Pius IX, while archbishop of Imola, was attributed to Philomena; in 1849, the Pope named her patroness of the Children of Mary. Pope Leo XIII approved the Confraternity of St. Philomena. Pope Pius X named St. John Vianney as the patron of this Confraternity because this saint had a strong and well-known devotion to her. Others with known devotion to her include St. Anthony Mary Claret, St. Euphrasia Pelletier, St. Francis Xavier Cabrini, St. John Nepomucene Neumann, St. Madeline Sophie Barat, St. Peter Chanel, St. Peter Julian Eymard, Blessed Anna Maria Taigi, and Venerable Pauline Jaricot who received a healing of her sickness from her.