The pope also known as the supreme pontiff (Pontifex Maximus), or the Roman pontiff (Romanus Pontifex), is the bishop of Rome, chief pastor of the worldwide Catholic Church, and head of state or sovereign of the Vatican City State.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, giving him the Keys of Heaven and the powers of "binding and loosing", naming him as the "rock" upon which the church would be built. Since 1929, the pope has official residence in the Apostolic Palace in the Vatican City, a city-state enclaved within Rome, Italy.The current pope is Francis, who was elected on 13 March 2013, succeeding Benedict XVI. While his office is called the papacy, the jurisdiction of the episcopal see is called the Holy See. It is the Holy See that is the sovereign entity by 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 Holy See is recognized by its adherence at various levels to international organization and by means of its diplomatic relations and political accords with many independent states. According to Catholic tradition, the apostolic see of Rome was founded by Saint Peter and Saint Paul in the 1st century. The papacy is one of the most enduring institutions in the world and has had a prominent part in world history. In ancient times the popes helped spread Christianity, and intervened to find resolutions in various doctrinal disputes. In the Middle Ages, they played a role of secular importance in Western Europe, often acting as arbitrators between Christian monarchs. Currently, in addition to the expansion of the Christian faith and doctrine, the popes are involved in ecumenism and interfaith dialogue, charitable work, and the defense of human rights. In some periods of history, the papacy, which originally had no temporal powers, accrued wide secular powers rivaling those of temporal rulers. However, in recent centuries the temporal authority of the papacy has declined and the office is now almost exclusively focused on religious matters. By contrast, papal claims of spiritual authority have been increasingly firmly expressed over time, culminating in 1870 with the proclamation of the dogma of papal infallibility for rare occasions when the pope speaks ex cathedra—literally "from the chair (of Saint Peter)"—to issue a formal definition of faith or morals.Still, the pope is considered one of the world's most powerful people because of his extensive diplomatic, cultural, and spiritual influence on 1.3 billion Catholics and beyond, and because he heads the world's largest non-government provider of education and health care, with a vast network of charities.