VATICAN CITY (AP) — Pope Leo XIV, history’s first American pope, has vowed to work for unity so that the Catholic Church becomes a sign of peace in the world. The 69-year-old Augustinian missionary offered a message of communion during an inaugural Mass in St. Peter’s Square before tens of thousands of people, presidents, patriarchs and princes. In his homily, Leo said he wanted to be a servant to the faithful through the two dimensions of the papacy: love and unity. His call for unity was significant, given the polarization in the Catholic Church in the United States and beyond.