The Acts of Sylvester are a series of legendary tales about the fourth-century bishop of Rome, Sylvester I. Sylvester was the bishop of Rome at the critical point in European history when Constantine the Great became the first Christian emperor. Yet, despite the claims that arose in later centuries of Roman primacy, some academics question whether Sylvester played a significant role in the Christianization of the Roman Empire during this crucial period. They contend these legends arose in order to augment the reputation of Sylvester and to correct a number of embarrassing events for the Church, such as his conspicuous absence at both the Synod of Arles in 314 and the First Council of Nicaea in 325, and the fact that Constantine had been baptized by an Arian bishop.

Pope Sylvester I was the bishop of Rome from 31 January 314 until his death on 31 December 335. He filled the See of Rome at an important era in the history of the Western Church, though very little is known of his life.