See of Rome in the context of "Old Catholic Church"

An apostolic see is an episcopal see whose foundation is attributed to one or more of the apostles of Jesus or to one of their close associates. In Catholicism, the phrase "The Apostolic See" when capitalized refers specifically to the See of Rome.

Tertullian (c. 155 − c. 240) gives examples of apostolic sees: he describes as churches "in which the very thrones of the apostles are still pre-eminent in their places, in which their own authentic writings are read, uttering the voice and representing the face of each of them severally" the following churches: Corinth, Philippi, Ephesus, and Rome.

Leo of Ohrid (Greek: Λέων Άχρίδος; died 1056) was a leading 11th-century Byzantine churchman as Archbishop of Ohrid (1037–1056) and advocate of the Ecumenical Patriarchate of Constantinople's views in the theological disputes with the See of Rome, which culminated in the East–West Schism of 1054.

Pope Sylvester I (also Silvester, before 284 – 31 December 335) 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.

During his pontificate, he notably convened the Council of Arles in 314, which condemned the separatist Donatist sect, and the First Council of Nicaea in 325, which aimed to resolve the Arian controversy. His pontificate also coincided with the baptism of Roman Emperor Constantine I.

Universi Dominici gregis is an apostolic constitution of the Catholic Church issued by Pope John Paul II on 22 February 1996. It superseded Pope Paul VI's 1975 apostolic constitution, Romano Pontifici eligendo, and all previous apostolic constitutions and orders on the subject of the election of the pope.

Universi Dominici gregis ("the Lord's whole flock", from the opening statement "The Shepherd of the Lord's whole flock is the Bishop of the Church of Rome"), subtitled On the Vacancy of the Apostolic See and the Election of the Roman Pontiff, deals with the vacancy of the See of Rome, i.e., the papacy. The constitution modified, or in some cases confirmed, the rules for the conclave. It also clarified, during a sede vacante, which matters could be handled by the College of Cardinals and which matters were reserved for the future pope.