Sidonius Apollinaris

Gaius Sollius Modestus Apollinaris Sidonius, better known as Sidonius Apollinaris, was a poet, diplomat, and bishop. Born into the Gallo-Roman aristocracy, he was son-in-law to Emperor Avitus and was appointed Urban prefect of Rome by Emperor Anthemius in 468. In 469 he was appointed Bishop of Clermont and he led the defence of the city from Euric, King of the Visigoths, from 473 to 475. He retained his position as bishop after the city's conquest, until his death in the 480s. He is venerated as a saint in the Catholic church, the Orthodox Church, and the True Orthodox Church, with his feast day on 21 August.
Sidonius is "the single most important surviving author from 5th-century Gaul" according to Eric Goldberg. He is one of four Gallo-Roman aristocrats of the 5th- to 6th-century whose letters survive in quantity; the others are Ruricius, bishop of Limoges, Alcimus Ecdicius Avitus, bishop of Vienne and Magnus Felix Ennodius of Arles, bishop of Ticinum. All of them were linked in the tightly bound aristocratic Gallo-Roman network that provided the bishops of Catholic Gaul.