A papal inauguration is a liturgical service of the Catholic Church within Mass celebrated in the Roman Rite but with elements of Byzantine Rite for the ecclesiastical investiture of a pope. Since the inauguration of Pope John Paul I, it has not included the 820-year-old (1143-1963) papal coronation ceremony.
Pope Paul VI, the last Pope to be crowned or to use a papal tiara, abandoned its use in a ceremony at the end of the Second Vatican Council, and announced that it would be sold and the money obtained would be given to charity; it was in fact bought by Catholics in the United States and is now kept in the Basilica of the National Shrine of the Immaculate Conception in Washington, D.C.. However, more than 20 other tiaras remain in the Vatican (see List of papal tiaras in existence). A small one is still used to symbolically crown a statue of Saint Peter on his saint's day every year. The first pope for over eight centuries to inaugurate his pontificate without a coronation was Pope John Paul I.
Read more about Papal Inauguration: Omission of The Coronation, The Modern Inauguration, Inauguration of Benedict XVI, The Future of The Inauguration Ceremony, List of Papal Inaugurations Since 1978