Hilary was born into a family of pagans of distinction. Only approximate dates of both his birth and death are known. He was born near the turn of the third to fourth century in Poitiers. He received a good education which included—a rarity for his day in the West—knowledge of Greek. He studied the [[scripture]]s of the [[Old Testament|Old]] and [[New Testament]] which led to his leaving Neoplatonism for Christianity. With his wife and daughter, Apra, he was [[baptize]]d in mid-life and received into the Church. His fame in Poitiers was such that the Christians unanimously elected him as their bishop at about 353.
These were the times when the Arian controversy was becoming intense in the Western Church. In his efforts against Arianism he fought to secure the excommunication of the Arian Saturtuinius as bishop of Arles as well as his two supporters, Uracius and Valens. He also wrote to Emperor Constantius II about the persecutions that the Arians were using against their opponents. His efforts received a setback when the Arian-dominated synod of 356 in Beziers, convened by Constantius, banished Hilary to Phrygia for almost four years for his strong defense of St. [[Athanasius of Alexandria]]. Hilary has often been referred to as "Athanasius of the West."
From exile he continued to lead his [[diocese]]. Also, he used this time to study the writing of the Eastern fathers and to write a number of dogmatic and polemical treatises presenting the [[First Council of
Nicaea|Nicene]] position to the Arians, one of which, ''On the Trinity'', was one of the first successful attempts to express the theological subtleties of the original Greek into the Latin. Hilary's agitation against the Arians while in exile resulted in the emperor ordering him back to Poitiers. He took his time returning, speaking along the way about the errors of the Arians. After his return from exile he continued actively challenging the Arians. In 359, Hilary attended a meeting of bishops at Seleucia in Isauria where he joined with Athanasius of Alexandria and the Homoiousians in a majority against the Arian party. Leaving Seleucia he continued to Constantinople to present the emperor with a petition setting out the arguments of the [[Trinitarian]]s. His constant requests for public discussion with the Arian party, especially Ursacius and Valens, resulted in his being sent back to his diocese.
He spent the later years of his life writing. He was also noted for composing many hymns. He died in 367 at a date not known. He was held in highest regard, even during his time, as a Latin writer of the highest rank. [[Augustine of Hippo]] already was referring to him as "the illustrious doctor of the churches."