Pope St. Julius I

Pope St. Julius I governed the Church of Rome from 337 to 352, in the thick of the great struggle over the Arian heresy that divided the Christian world after the Council of Nicaea. He is remembered above all as a steadfast defender of St. Athanasius of Alexandria, the champion of orthodox faith, who, driven from his see by the Arians, appealed to Rome; Julius received him, examined his cause, and declared him innocent, upholding his restoration.

When the Eastern bishops who favored Arianism protested, Julius wrote them a firm and celebrated letter asserting the right of appeal to the See of Peter and rebuking them for acting without reference to Rome, an important witness to the authority of the Roman Church in the affairs of the whole Christian body. He also worked to strengthen the organization and worship of the Church in the city, and tradition credits him with fixing the celebration of the Lord's Nativity on 25 December. He died in 352, and his memory is kept on 12 April.