As the Roman nomenclature system began to break down towards the end of the Western Empire in the 4th and 5th centuries, Faustus once again became a personal name, and it has survived into modern times.
[1][2] The best-known examples of this praenomen are from the family of the dictator Lucius Cornelius Sulla, who in 81 B.C.
Other gentes from which examples are known include the Antistii, Decimii, Lartii, Paccii, Veidii, and Vibii; and perhaps also the Julii, Servii, and Sestii.
Another interesting example mentioned in the Realencyclopädie der Classischen Altertumswissenschaft was of two brothers named Faustus and Fortunatus.
However, Fortunatus probably was not a genuine praenomen, but was chosen on that occasion simply because it was a synonym of Faustus.