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Pope Leo XIV’s inauguration mass has begun in St Peter’s Square, attended by hundreds of dignitaries, including President Michael D Higgins, and thousands of people.
Shortly before the mass began, the Pope made his first tour of St Peter’s Square in his popemobile, smiling and waving to the crowds.
The Catholic Church’s first US-born pontiff stood in the white vehicle as it drove among tens of thousands of flag-waving and cheering people at the Vatican.
Crowds filled the square and surrounding streets in Rome for the formal celebration, which started at 10am local time (9am Irish time).
Born in Chicago, the 69-year-old pontiff spent many years as a missionary in Peru and also has Peruvian citizenship, meaning he is also the first pope from that South American nation.
Robert Prevost, a relative unknown on the world stage who only became a cardinal two years ago, was elected Pope on 8 May after a short conclave of cardinals that lasted barely 24 hours.
President Michael D Higgins and his wife, Sabina, are leading the Irish delegation at the event.
Speaking after Pope Leo’s election, President Higgins wished the pontiff “success and strength” for his papacy.
President Higgins said it was his “sincere hope” that under Pope Leo’s leadership, the Holy See will “continue to play a central role in promoting global solidarity, addressing the pressing issues of poverty, inequality, conflict, and climate change”.
US Vice President JD Vance, a Catholic convert who clashed with Pope Francis over the Trump administration’s immigration policies, is leading a US delegation alongside Secretary of State Marco Rubio, who is also Catholic.
Ukrainian President Volodymyr Zelensky is also attending and would be happy to meet other leaders, a top aide said, as he did at Pope Francis’s funeral when he had face-to-face talks with US President Donald Trump in St Peter’s Basilica.
Mr Zelensky last met Mr Vance in February in the White House, when the two men clashed in front of the world’s media.
Also expected at the Vatican ceremony are the presidents of Peru, Israel and Nigeria; the prime ministers of Italy, Canada and Australia; German Chancellor Friedrich Merz and European Commission President Ursula von der Leyen.
Many European royals will also be in the VIP seats near the main altar, including Spanish King Felipe and Queen Letizia.
In various sermons and comments since his election, the Pope has praised Francis repeatedly but has not offered many hints about whether he will continue with the late pontiff’s vision of opening the Church up to the modern world.
His homily is likely to indicate some of the priorities for his papacy, having already made clear over the past ten days that he will push for peace whenever possible.
His first words in an appearance to crowds in St Peter’s Square on the night of his election were “peace be with you all”.
In an address on 14 May to officials of the eastern Catholic Churches, many of whom are based in global hot spots such as Ukraine and the Middle East, the new pontiff pledged he would make “every effort” for peace.
He also offered the Vatican as a mediator in global conflicts, saying war was “never inevitable”.
The mass will feature prayers in several languages, in a nod to the global reach of the 1.4-billion member church, including Latin, Italian, Greek, Portuguese, French, Arabic, Polish and Chinese.
As part of the ceremony, Pope Leo will also formally receive two items as he takes up the papacy: a liturgical vestment known as a pallium, a strip of lambswool which represents his role as a shepherd, and a special band known as the fisherman’s ring.
The ceremonial gold signet ring is specially cast for each new pontiff and can be used by Pope Leo to seal documents.
It features a design of St Peter holding the keys to heaven and will be broken after his death, marking an end to his papacy.
