The tenure of Pelagius I, as Pope, was marked by tumultuous events associated with the aftermath of his election as the successor to Vigilius. During Vigilius' pontificate, Pelagius served the Church as a Deacon and later as the apostolic Nuncio of Constantinople.

Justinian the Emperor through his authority appointed Pelagius as the successor to Pope Vigilius. This appointment was looked upon with utter dissatisfaction by the Church leadership in Rome and the ecclesiastical community. Pelagius found himself in severe opposition from both the leadership and the faithful upon his arrival in Rome. Despite efforts to legitimize Pelagius' election through the correct path, he faced strong opposition from monks, nobles, and clergy.

The College of Bishop disagreed to accept Pelagius I as pope and to enthrone him as the Successor to Peter. However, in AD 556, he was enthroned as the Sixtieth Pontiff by two bishops, one among them, the Bishop of Ostia.

Despite accusations of his loyalty to Emperor Justinian, right after his enthronement, Pelagius I publicly swore his allegiance to the teachings of the Universal Councils of Nicaea, Constantinople, Ephesus, and Chalcedon.

Pelagius I solemnly swore on the Holy Bible and Crucifix that he had not caused any harm to his successor, Pope Vigilius I. His strong stance thus earned him respect and support from other ecclesiastical leaders.

Pelagius I's endured to restore peace and stability in Italy and Rome which have been ravaged due to relentless conflicts and war. He laboured tirelessly to provide special assistance to the poor, eradicate famines, and free prisoners of war.

Pelagius I also reformed the papal wealth distribution system and distributed the income from papal properties in Italy, Gaul, Dalmatia, and North Africa to the poor. The Pontiff took a strong stand against corruption among the clergy, where spiritual gifts and positions in the church were acquired for money and sold by church officials, reacting with intolerance towards such systems.

Despite his sincere efforts, Pelagius I's tenure as pope was marked by continuous opposition and challenges from both within and outside the Churches in Rome. He continued to be looked upon with hatred and hostility by the church leadership and faithful.

Pelagius I's positions taken on the "Three Chapters" Controversy was the main reason for the widespread opposition he faced. Prominent figures like Milan and Aquileia's bishops and the Church in Gaul openly expressed their disapproval and denied to accept him as the Supreme Pontiff.

Pope Pelegius I, who was well into his old years when he was consecrated pope, led the church for about five years. He passed away on 4th March AD561. His mortal remains were laid to rest in St. Peter's Basilica.