Tradition makes him a prince of Ireland who became a hermit on Mount Pisano, near Lucca, after going on pilgrimage to Rome. The Catholic Encyclopedia states: “Remarkable for sanctity and miracles was St. Fridianus (560-88), son of Ultonius, King of Ireland, or perhaps of a king of Ulster (Ultonia), of whom in his "Dialogues" (III, 10) St. Gregory the Great relates a miracle.”
Tradition states that he was appointed bishop of Lucca by the pope. During his episcopate, Lucca was attacked by the Lombards. He may have founded a group of eremetical canon priests; these canons merged with the Canons Regular of the Lateran in 1507.
Fridianus had a church built on the spot of the present basilica, dedicated to St. Vincent, a martyr from Zaragoza, Spain. When Fridianus was buried in this church, the church was renamed Ss. Frediano and Vincenzo.