Pope Leo XIV will preside over his inaugural mass Sunday, May 18, with world leaders and large crowds expected to gather in St. Peter’s Square at the Vatican. Following the death of Pope Francis on April 21, a conclave commenced May 7, bringing together a private group of cardinals tasked with voting for a new leader of the Roman Catholic Church.

In his public appearance as pope, Leo called himself an Augustinian, putting an unusual spotlight on his religious order.