The Pope is Pontifex Maximus (greatest priest), Bishop of Rome, Leader of the worldwide Catholic Church, and the head of state of Vatican City (city-state) a recognized country withing the city of Rome.

Holy See that is the sovereign entity of international law headquartered in the distinctively independent Vatican City State, established by the Lateran Treaty in 1929 between Italy and the Holy See to ensure its temporal, diplomatic, and spiritual independence. The Pope is the head of Admiralty Law.