St. Sylvester, born in Rome, was ordained by Pope St. Marcellinus during the peace that preceded the persecutions of Diocletian. He passed through those days of terror, witnessed the abdication of Diocletian and Maximian, and saw the triumph of Constantine in the year 312. Two years later he succeeded St. Melchiades as Bishop of Rome. In the same year, he sent four legates to represent him at the great Council of the Western Church, held at Aries. He confirmed it's decision and imparted them to the Church.
The Council of Nice was assembled during his reign, in the year 325, but not being able to assist at it in person, on account of his great age, he sent his legates, who headed the list of subscribers to its decrees, preceding the Patriarchs of Alexandria and Antioch. St. Sylvester was Pope for twenty-four years and eleven months. He died in the year 335. His Feast Day is December 31st.