Member of the aristocratic samily of the Symmachi, he was the son of Aurelius Valerius Tullianus Symmachus, consul for 330. He had one daughter and four sons, among which Celsinus Titianus and the most influential of the Symmachi, the orator Quintus Aurelius Symmachus. Avianius was a pagan senator, and was member of several priestly collegia, among which the Pontefices Vestae and the Quindecemviri sacris faciundi (from 351 to 375).
Before January 350 he had been appointed prefect to the annona, later he became vicarius urbis Romae. In 361, he went to Antioch (in Syria), where he probably met Libanius, to meet Emperor Constantius II: it is probable that the Roman Senate wanted to assure its loyalty to the ruling emperor after receiving a letter from Julian, cousin and caesar of Constantius who ahd been just proclaimed emperor by his troops. On their way back, Symmachus and his colleague Valerius Maximus travelled through Nassus, where they were received by Julian with all the honours.
Between 364 and 365 he held the office of praefectus urbi of Rome, under the rule of Valentinian I. As praefect, he restored the ancient pons Agrippae on the Tiber (on the place of the modern Ponte Sisto), which took the name of pons Valentiniani; Symmachus even payed for a lavish public celebration for the inauguration of this bridge. Ammianus Marcellinus has a flattering opinion of his mandate.
His house was on the right side of the Tiber, in Trastevere, and was burned down by the plebs during a riot in 377. According to the story told by Ammianus, the riot originated from a rumor, diffused by a member of the plebs, according to which Symmachus, during his prefecture, had said that he "preferred to slake lime with wine, rather than selling it at the price wanted by the plebs"; forgetting the prosperity achieved during Symmachus' office, the enraged plebs burnt down his house. Avianio left the city following this offence caused by "envy", that he tried to heal writing a literature work. After a while, however, the plebs changhed their mind and started supporting Symmachus, even asking for a punishment of the violents. Symmachus returned in Rome, by request of the Roman Senate, whom he thanked on 1 January 376; the senators, even the Christians, proposed him to Emperor Gratian as praetorian prefect and consul for year 377.
Avianius Simmachus is described by his son as a reader of evrey kind of literature. He composed a small number of epigrams of low quality about members of the Constantinian age, such as Amius Anicius Iulianus and Lucius Aradius Valerius Proculus.
- Jones, Arnold Hugh Martin, John Robert Martindale, John Morris, The Prosopography of the Later Roman Empire, volume 1, Cambridge University Press, 1992, ISBN 0521072336, p. 869.
- Mazzarino, p. 412.
- Rüpke, Jörg, Fasti Sacerdotum, Franz Steiner Verlag, 2005, ISBN 3515074562, pp. 512-529.
- Ammianus Marcellinus, xxi.12.24; CIL, VI, 1698.
- Sogno, pp. 3-4.
- CIL, VI, 31403, 31404.
- Ammianus Marcellinus, xxvii.3.3-4.
- Kahlos, Chapter 12 "A senatorial life"; Lawrence Richardson, A New Topographical Dictionary of Ancient Rome, JHU Press, 1992, ISBN 0801843006, p. 135.
- It was proposed that the riot had had a political purpose, being a mean to put pression on Symmachus (Lizzi Testa).
- Symmachus, Orationes, v.1.
- Symmachus, Epistulae, i.2.2.
- Mazzarino, p. 411.
- Symmachus, Epistulae, i.44.2.
- Sogno, p. 77.
- Salzman, Michele Renee, The Making of a Christian Aristocracy, Harvard University Press, 2002, ISBN 0674006410, pp. 58-59.
- Kahlos, Chapter 3 "Cultural pursuits".
- Primary sources
- Quintus Aurelius Symmachus, Epistulae, i.1-12 (addressed to his father); Orationes, iv (pro patre) e v (pro Trygetio)
- Ammianus Marcellinus, Res Gestae xxxi libri, xxi.12.24, xxvii.3.3-4.
- Secundary sources
- Kahlos, Maijastina, Vettius Agorius Praetextatus - Senatorial Life in Between, Acta Instituti Romani Finlandiae n. 26, Roma 2006.
- Lizzi Testa, Rita, Senatori, popolo, papi: il governo di Roma al tempo dei Valentiniani, EDIPUGLIA, 2004, ISBN 8872283922, pp. 327-333.
- Mazzarino, Santo, Antico, tardoantico ed èra costantiniana, Edizioni Dedalo, 1980, ISBN 8822005139, pp. 410-414.
- Sogno, Cristiana, Q. Aurelius Symmachus: A Political Biography, University of Michigan Press, 2006, ISBN 0472115294
- Wace, Henry, "Symmachus (3) Q. Aurelius", Dictionary of Christian Biography and Literature to the End of the Sixth Century A.D., with an Account of the Principal Sects and Heresies, Hendrickson Publishers, Inc., 1999 , ISBN 1-56563-460-8