Catholic Encyclopedia entry:
Unanimously elected Bishop of Carthage in 480 to succeed Deogratias (d. 456); d. 13 July, 505. The election was deferred owing to the opposition of the Arian Vandal kings and was only permitted by Huneric at the instance of Zeno and Placidia, into whose family the Vandals had married. The bishop's wise government, charity to the poor, austerity of life, and courage underpersecution, won the admiration of the Arians. In his uncompromising defence of the Divinity of the Word he was imitated by the members of his flock, many of whom were exiled with him, after he had admitted Vandals into the Catholic Church, contrary to royal edict, and had worsted in argument Arian theologians, whom the king pitted against the Catholics. Both sides claimed the name "Catholic", the Arians calling their opponents "Homoousians". The conference was held some time between 481 and February, 484, and ended by the withdrawal of the chief Arian bishop on the plea that he could not speak Latin. TheArians being enraged, Huneric persecuted the Catholics, exiling forty-six bishops to Corsica, and three hundred and two to theAfrican deserts. Among the latter was Eugenius, who under the custody of a ruffian named Antonius dwelt in the desert of Tripoli. On setting out he wrote a letter of consolation and exhortation to the faithful of Carthage which is still extant in the works of Gregory of Tours (P.L., LVII, 769-71). Gunthamund, who succeeded Huneric allowed Eugenius to return to Carthageand permitted him to reopen the churches. After eight years of peace Thrasamund succeeded to the throne, revived thepersecution, arrested Eugenius, and condemned him to death, but commuted the sentence into exile at Vienne, near Albi(Languedoc), where the Arian Alaric was king. Eugenius built here a monastery over the tomb of St. Amaranthus, the martyr, and led a penitential life till his death. He is said to have miraculously cured a man who was blind.
He wrote: "Expositio Fidei Catholicae", demanded of him by Huneric, probably the one submitted by the Catholic bishops at the conference. It proves the consubstantiality of the Word and Divinity of the Holy Ghost. He wrote also an "Apologeticus pro Fide"; "Altercatio cum Arianis", fragments of which are quoted by Victor de Vita; also pleas for the Catholics, addressed to Huneric or his successors. His letter to the faithful of Carthage has been mentioned above.