Porfirius was born in the second half of the 3rd c., probably between 260 and 270 AD. Evidence for this dating comes from a horoscope reported by Firmicus Maternus, which most likely refers to our author (Math. 2.29.10); an inscription from Rome (Notizie degli scavi di antichità 1917, 1 p. 22 [fr. 1]); another inscription from Sparta (Supplementum epigraphicum Graecum XI 810 = Année épigraphique 1931, 6;); the so-called Chronography of 354 (Mommsen, Chronica minora, MGH aa IX 1, p. 68); the entry for the year 329 in Jerome’s Chronicle; and the author’s own works. The last of these provide us with secure attestations of the author’s name and include letters crossings that guarantee its original spelling.
Porfirius’ father was Junius Tiberianus, a man twice consul (281 and 291) and prefect of Rome (291). His older brother, who shared the name with their father, was proconsul of Asia and prefect of Rome (303-304). The neoplatonic poet Tiberianus, a few of whose compositions survive to us, also appears to have been from the same family. Porfirius was himself a senator and member of the pagan clique under Maxentius; he was probably coopted to the priesthood of the quindecemviri sacris faciundis, was married, and had one son. After his youth, he participated - perhaps as a comes of Constantine - in the expedition against the Sarmatians in 322. A little later, between 322 and 323, he was sent into exile - probably at Siga in Africa - after being accused of practicing magic and being charged with a crimen adulterii. He composed the majority of his elaborate carmina figurata during the period 324-5, though some of these are decidedly older (one can be dated to 320-1, and a few others are decidedly earlier even if they cannot be dated with precision), and sent them to the emperor as part of a request for pardon, which was granted in 325 during the twentieth anniversary of the emperor’s ascension. After returning to Rome, he held respected positions in the imperial administration, first at Campania, then as proconsul of Achaea (327), proconsul of Asia (328), and prefect of Rome (329 and 333, though only for short periods in both cases). His death can be placed c. 333-337 on the basis of the horoscope published by Firmicus Maternus. This makes it clear that the individual he is describing had already died, and although he prudently and discretely maintains his anonymity, he nevertheless does so in a way that did not prevent contemporaries from identifying him (cuius haec genitura sit, Lolliane decus noster, optime nosti). Porfirius, in any event, had already lived sixty years and suffered poor health (cum multis corporis vitiis… multis valetudinibus oppressum).
Besides the carmina figurata, for which he invented a new technique destined to enjoy great popularity in the middle ages, the sources that have transmitted his works reveal that he also composed a letter to Constantine; this latter text, however, cannot be dated securely to the period of exile and is of doubtful authenticity (as is the emperor’s response, which is likewise preserved in the manuscripts). The carmina are accompanied by scholia that appear to be the work of various authors; while some of these could have been composed by Porfirius himself, no decisive arguments in favor of that attribution have yet been made. [G. Polara; tr. C. L. Caterine].