Avitus, Alcimus Ecdicius , archbp. of Vienne in Narbonian Gaul; born about the middle of 5th cent. His father belonged to a family of senatorial rank. His mother, Audentia, was, in all probability, a sister of M. Maecilius Avitus, emperor of the West, A.D. 456. The mother of Sidonius Apollinaris the poet, who, in a letter to Alcimus Avitus, speaks of their near relationship and the identity of their youthful pursuits, seems to have been another sister of the same illustrious family (Sidon. Apoll. Ep. iii. 1, 61). A student's life attracted Avitus more than did wealth and rank, and at an early age he bestowed his patrimony upon the poor and retired into the seclusion of a monastery close to the walls of his native city. Here he gained so high a reputation for piety and learning that in 490 A.D., upon the death of his father, he was elected to succeed him in the archbishopric. The fame of Avitus rests partly upon his poetry and partly upon the important part he was called to play in the controversies of his time. In 499 Vienne was captured by Gundobald, king of the Burgundians, who was at war with Clovis, king of the Franks; and Avitus, as metropolitan of S. and E. Gaul, took the lead in a conference between the Catholic and Arian bishops held in presence of Gundobald at Sardiniacum near Lyons (Greg. Turon., ii. 34). The king was convinced by the earnest entreaties and powerful reasoning of Avitus, who addressed several extant letters to him, but could never be induced to recant his errors publicly. His successor Sigismund was converted by Avitus from Arianism.

Avitus published treatises in confutation of the Nestorian, Eutychian, and Sabellian heresies; he also wrote against the Pelagian errors of Faustus, abbot of Lerins, and converted many Jews who had settled in his diocese (Venant. Fortun. l. v. c. 5).

From a letter of pope Hormisdas to Avitus (Ep. x.) we gather that he was made vicar apostolic in Gaul by that pontiff; and in A.D. 517 he presided in this capacity at the council of Epaune (Concilium Epaonense) for the restitution of ecclesiastical discipline in Narbonian Gaul. But his influence seems to have extended far beyond the limits of his own diocese, as is shewn by his correspondence with several historical personages at Rome, e.g. Faustus, Symmachus, Vitalianus, etc. He appears also to have exerted himself to terminate the dispute between the churches of Rome and Constantinople which arose out of the excommunication of Acacius; that this was accomplished before his death we gather from his letters ( Epp. iii, vii.).

Avitus died Feb. 5, 523, and was buried in the monastery of St. Peter and St. Paul at Vienne, where the greater part of his youth had been spent.

The extant works of St. Avitus are as follows: A poem in five books on subjects drawn from Genesis and Exodus: de Origine Mundi; de Peccato Originali; de Sententia Dei; de Diluvio; de Transitu Maris Rubri, this is dedicated to his brother Apollinaris, and consists of 2611 hexameter lines. The first three books might almost have suggested the idea of Milton's Paradise Lost , to which they bear a curious and in many points interesting analogy. A collection of 91 letters, several of historical interest, especially that addressed to Clovis (Ep. xli.) upon his baptism. A homily, de Festo Rogationum , from which the religious observance of Rogation days took its origin. [See Mamertus.] A second homily representing the Rogation of the third day, which was discovered in the library of the Grande Chartreuse, and first published in 1717 by Dom Marten (Thesaur. Anecd. p. 47). A homily preached on the occasion of the dedication of a church erected by Maximus, bp. of Geneva. Seventy-two short fragments of homilies, sermons, etc. The Collatio Episcoporum contra Arianos coram Gundobaldo rege , first published in d’Achery's Spicilegium , 1655 ff. (tom. iii. p. 304, ed. Paris, 1725). These remains contain much that is valuable with reference to the history, doctrine, and discipline of the church in the 5th cent. The works of Avitus are contained in Migne's Patrologia , vol. lix. Oeuvres , ed. N. Chevallier (Lyons, 1890).