Head of the Church in the context of "Roman Pontiff"

The pope is the bishop of Rome and the head of the worldwide Catholic Church. He is also known as the supreme pontiff, Roman pontiff, or sovereign pontiff. From the 8th century until 1870, the pope was the sovereign or head of state of the Papal States, and since 1929 of the much smaller Vatican City State. From a Catholic viewpoint, the primacy of the bishop of Rome is largely derived from his role as the apostolic successor to Saint Peter, to whom primacy was conferred by Jesus, who gave Peter the Keys of Heaven and the powers of "binding and loosing", naming him as the "rock" upon which the Church would be built. The current pope is Leo XIV, who was elected on 8 May 2025 on the second day of the 2025 papal conclave.

While his office is called the papacy, the jurisdiction of the episcopal see is called the Holy See. The word see comes from the Latin for 'seat' or 'chair' (sede, referring in particular to the one on which the newly elected pope sits during the enthronement ceremony). The Holy See is a sovereign entity under international law; it is headquartered in the distinctively independent Vatican City, a city-state which forms a geographical enclave within the conurbation of Rome. It was established by the Lateran Treaty in 1929 between Fascist Italy and the Holy See to ensure its political and spiritual independence. The Holy See is recognized by its adherence at various levels to international organizations and by means of its diplomatic relations and political accords with many independent states.

A cardinal is a senior member of the clergy of the Catholic Church. As titular members of the clergy of the Diocese of Rome, they serve as advisors to the pope, who is the bishop of Rome and the visible head of the worldwide Catholic Church. Cardinals are chosen and formally created by the pope, and typically hold the title for life. Collectively, they constitute the College of Cardinals. The most solemn responsibility of the cardinals is to elect a new pope in a conclave, almost always from among themselves, with a few historical exceptions, when the Holy See is vacant.

During the period between a pope's death or resignation and the election of his successor, the day-to-day governance of the Holy See is in the hands of the College of Cardinals. The right to participate in a conclave is limited to cardinals who have not reached the age of 80 years by the day the vacancy occurs. With the pope, cardinals collectively participate in papal consistories, in which matters of importance to the Church are considered and new cardinals may be created. Cardinals of working age are also often appointed to roles overseeing dicasteries (departments) of the Roman Curia, the central administration of the Catholic Church.