The Pope (from Greek: pappas, "father", via Latin: papa) is the head of the Catholic Church. His ecclesiastical jurisdiction is called the Holy See (Sancta Sedes in Latin) or Apostolic See (this latter, on the basis that both St. Peter and St. Paul were martyred at Rome). Early bishops occupying the See of Rome were designated Vicar of Peter; for later popes the more authoritative Vicar of Christ was substituted; this designation was first used by the Roman Synod of 495 to refer to Pope Gelasius I, an advocate of papal supremacy among the patriarchs. Marcellinus (d. 304) is first Bishop of Rome which sources show used the title of pope. The current Pope is Benedict XVI, who was elected in 2005
In addition to his service in this spiritual role, the pope is also head of state of the independent sovereign state of the Vatican City, a city-state and nation entirely enclaved by the city of Rome. Prior to 1870 the pope's temporal authority extended over a large area of central Italy, the territory of the Papal States. Although the document on which the territorial powers of the Pontificate was based — the so-called Donation of Constantine — was proved to be a forgery in the fifteenth century, the Papacy retained sovereign authority over the Papal States until the Italian Unification of 1870; a final political settlement with the Italian government was not reached until the Lateran Treaties of 1929.