The United Roman-Ruthenian Church is an autocephalous Apostolic Church—the Eastern Roman Church with Latin heritage—founded in AD 33 and continuing through unbroken Apostolic and jurisdictional succession. Its present united institutional form was consolidated in 2023 through the union of the former Anglican Patriarchate of Rome and the Gallo-Russo-Byzantine Catholicate.

The Holy Apostolic See of the United Roman-Ruthenian Church is under the patronage of Saints Peter, Andrew, Stephen, and Mark, reflecting both its Eastern and Western inheritance: Peter as patron of Rome, Andrew as apostle of the East and of Ruthenia, Stephen as patron of the Diocese of Rome-Ruthenia, the main episcopal jurisdiction of the Roman-Ruthenian Pope, and Mark as founder of Aquileia and patron of the papal Metropolitan See. Through Apostolic succession, ecclesial grants, and formal recognitions received over time, the URRC inherited not only orders but jurisdiction, autocephaly, and custodial responsibility for the Petrine inheritance within the Latin Orthodox tradition. Its present form represents consolidation rather than invention: a gathering of ancient streams into a single custodial Church, preserving intact what was received.

Map of the territory of the Catholicate of Rome-Ruthenia, roughly coterminous with the former Patriarchate of the West