Phoebadius an eminent prelate of the 4th century, flourished as bishop of Agen, in Gaul. He was living in 392, when Jerome wrote his Catalogue, but was then in extreme old age. He is noted as the author of Liber contra Arianos (published in Bibl. Max. Patr. 4:300; Bibl. Patr. Gall. 5:250; Athanasii Dialogi, 5:1570, 8vo).