|Papacy began||17 May 3521|
|Papacy ended||24 September 366|
|Died||24 September 366|
|Papal styles of
|Reference style||His Holiness|
|Spoken style||Your Holiness|
|Religious style||Holy Father|
He is not mentioned as a saint in the Roman Martyrology. His first recorded act was, after a synod had been held at Rome, to write to Emperor Constantius II, then in quarters at Arles (353–354), asking that a council might be called at Aquileia with reference to the affairs of Athanasius of Alexandria, but his messenger Vincentius of Capua was compelled by the emperor at a conciliabulum held in Arles to subscribe against his will to a condemnation of the orthodox patriarch of Alexandria.
At the end of an exile of more than two years in Thrace, after which it seems he may have temporarily relented to the Arian cause, or been set up to appear to have relented – partially evidenced by three letters, quite possibly forgeries, ascribed to Liberius, the emperor recalled him, but, as the Roman See was officially occupied by Antipope Felix II, a year passed before Liberius was sent to Rome. It was the emperor's intention that Liberius should govern the Church jointly with Felix, but on the arrival of Liberius, Felix was expelled by the Roman people. Neither Liberius nor Felix took part in the Council of Rimini (359).
After the death of the Emperor Constantius in 361, Liberius annulled the decrees of that assembly but, with the concurrence of bishops Athanasius and Hilary of Poitiers, retained the bishops who had signed and then withdrew their adherence. In 366, Liberius gave a favourable reception to a deputation of the Eastern episcopate, and admitted into his communion the more moderate of the old Arian party. He died on 24 September 366.
Pope Pius IX noted in Quartus Supra that Liberius was falsely accused by the Arians and he had refused to condemn Athanasius of Alexandria. In his encyclical Principi Apostolorum Petro, Pope Benedict XV noted that Pope Liberius went fearlessly into exile in defence of the orthodox faith. 
In the Eastern Orthodox Church, he is a saint whose feast is celebrated on August 27.
- "Pope Liberius". Catholic Encyclopedia. New York: Robert Appleton Company. 1913.
- Byfiend, Ted, ed. Darkness Descends, pg. 35
- "Abdication". Catholic Encyclopedia. New York: Robert Appleton Company. 1913.
- "On Monday, August 27, 2012 we celebrate". Online Chapel. Greek Orthodox Archdiocese of America. Retrieved August 14, 2012.
- This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Liberius". Encyclopædia Britannica (11th ed.). Cambridge University Press.
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|Catholic Church titles|
|Bishop of Rome