Pope Pelagius I (d. 4 March 561) was Pope from 556 to his death in 561. He was the second pope of the Byzantine Papacy, and like his predecessor, a former apocrisiarius to Constantinople.
Pelagius was elected Pope as Justinian's candidate, a designation not well received by the western clergy and laity. While before his ordination he opposed Justinian's efforts to condemn the "Three Chapters" in order to reconcile theological factions in the Church, afterwards Pelagius adopted Justinian's position.
Rumors that he might have somehow been complicit in the death of Virgilius, and suspicion that his conceding to Justinian indicating a support for Monophysitism undermined his papacy. To overcome this he worked to maintain public order in Rome, and correct abuses among the clergy. He also labored on behalf of the poor and the victims of famine and war. In response to a request from the garrison commander at Civitavecchia, Pelagius directed Bishop Lawrence of that town, to provide chaplains for the army. He is credited with the construction of the Santi Apostoli, Rome, built to celebrate the complete victory of Narses over the Ostrogoths.
The elderly pope served five years, and upon his death was buried in St. Peter's.