Bp. of Rome from 314 to 335. Little is known of him. Later legend asserts that he baptized Constantine (cleansing him from physical leprosy) at the Baptistery of the Lateran and established the Lateran church as the cathedral of Rome on land given him by the Emperor. He is also the reputed recipient of the Donation of Constantine. Feast day in the W., 31 Dec.; in the E., 2 Jan.