The Diocese of Rome (, ) is a diocese of the Catholic Church in Rome. Its bishop, known as the Pope, is the Supreme Pontiff and leader of the Catholic Church. As the Holy See, it is a sovereign entity with diplomatic relations, and civil jurisdiction over the Vatican City State within Rome. The Diocese of Rome is the metropolitan diocese of the Province of Rome, an ecclesiastical province in the Episcopal Conference of Italy. The Catholic Church teaches that the first Bishop of Rome was Saint Peter in the first century; the incumbent since 13 March 2013 is Pope Francis.