Vatican LIVE: New Pope Leo XIV and Other Cardinals Gather for a Mass in the Sistine Chapel Newly elected Pope Leo XIV celebrates mass with cardinals in sistine chapel In a historic moment for the Catholic Church, Cardinal Robert Prevost, a 69-year-old missionary and head of the Vatican’s influential office of bishops, has been elected pope, becoming the first American to hold the papacy in the Church’s 2,000-year history Prevost, who spent much of his clerical career ministering in Peru, chose the papal name Leo XIV following his election. Prevost’s election came after the conclave of cardinals convened to select a successor to Pope Francis. White smoke billowed from the chimney of the Sistine Chapel earlier and the great bells of St. Peter’s Basilica rang out, signaling that cardinals had elected the 267th pope on the second day of their conclave.