The Vatican has announced that Pope Leo XIV will be formally installed as pontiff during an inaugural Mass at St. Peter’s Square on Sunday, May 18, at 10 a.m. This ceremonial event comes just over a week after the historic election of the first American pope in the Catholic Church’s two-millennium history.
St. Peter’s Square (Piazza San Pietro), designed by Gian Lorenzo Bernini between 1656 and 1667, spans 320 meters long and 240 meters wide, with a capacity to hold up to 300,000 people. The massive open-air plaza is framed by a colonnade consisting of 284 columns arranged in four rows. Atop the structure are 140 statues of saints sculpted in 1670 by Bernini’s disciples. These colonnades create what Bernini described as “the maternal arms of the Church.”
The 69-year-old Chicago-born pontiff, formerly Cardinal Robert Prevost, celebrated his first Mass as pope in the Sistine Chapel on May 9, though that service was reserved exclusively for the cardinals who elected him. Unlike that private ceremony, the upcoming inauguration will be open to the public and attended by political and religious leaders from around the world.
The ceremony will feature the bestowal of the pallium, a white woolen band adorned with crosses symbolizing the pope’s universal jurisdiction. This tradition has replaced the more elaborate papal coronations of the past—Pope Paul VI was the last to wear the traditional tiara.
Following his inauguration, Pope Leo XIV faces a packed schedule, including taking possession of Rome’s three major basilicas: St. Paul Outside the Walls on May 20, and St. John Lateran and St. Mary Major on May 25. He’ll also hold his first general audience on May 21 and meet with the Roman Curia and Vatican City State employees on May 24.

Julia Cancilla is the engagement editor (and resident witch) at ELLE Decor, where she manages the brand’s social media presence and covers trends, lifestyle, and culture in the design world. Julia built her background at Inked magazine, where she grew their social media audiences by two million, conducted interviews with A-list celebrities, and penned feature articles focusing on pop culture, art and lifestyle. Over her five years of digital media experience, Julia has written about numerous topics, from fashion to astrology.