The name Rufius Festus is attested in the manuscript tradition of his Breuiarium. The most authoritative manuscripts are unanimous in reporting the cognomen as Festus. Variants are attested for his nomen gentile (Rufius, Rufus, Ruffus, Sextus Rufus, Rufinus, Rufus Avienius). The form Rufius is apparently to be preferred. A few manuscript designate him as uir clarissimus, which implies that he was an official in the Imperial administration. The codex Bambergensis states that he was magister memoriae of the emperor; we are not sure whether we can credit this piece of information.  We can date his life to the central part of the fourth century AD on the basis of chronological data present in his work. The Breuiarium itself was probably written after Valens’ victory against the Goths and in the period of the joint reign of Valens and Valentinan I (369-375 AD). The final chapter of Breuiarium seems to attest that its author was of an advanced age (aeuo grauior) when he wrote it. Attempts have been made to identify the author of the Breuiarium with otherwise known contemporary persons. The focus is on two people: the poet Rufius Festus Auienus, who translated the Aratea and wrote other poetical works of scientific-geographic character (Pithou; Mommsen suggests that the author of the Breuiarium was the son of the poet); the Festus (or Festinus) Tridentinus who is mentioned by Ammianus Marcellinus (29, 2, 21) as an intimate friend of Maximinus, as well as governor of Syria, magister memoriae, and proconsul Asiae in the 370s (Wagener, Herzog). Both suggestions have been now called into doubt (Den Boer, Baldwin). [R. Tabacco; translation L. Battezzato]