Pope Gelasius I
Pope Gelasius I was the bishop of Rome from 1 March 492 to his death on 19 November 496. Gelasius was a prolific author whose style placed him on the cusp between Late Antiquity and the Early Middle Ages. His predecessor Felix III employed him especially in drafting papal documents. During his pontificate he called for strict Catholic orthodoxy, more assertively demanded obedience to papal authority, and, consequently, increased the tension between the Western and Eastern Churches.
The feast of Saint Valentine of February 14 was first established in 496 by Pope Gelasius, who included Valentine among all those "... whose names are justly reverenced among men, but whose acts are known only to God."