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, offering a message of love and communion during an inaugural Mass in St Peter's Square before tens of thousands of people, presidents, patriarchs and princes.
Leo officially opened his pontificate by taking his first popemobile tour through the piazza, a rite of passage that has become synonymous with the papacy's global reach and mediatic draw. The 69-year-old Augustinian missionary smiled and waved from the back of the truck, but didn't appear to stop to kiss babies and the crowd.
During the Mass, Leo appeared to choke up when the two potent symbols of the papacy were placed on him — the pallium woolen stole over his shoulders and the fisherman's ring on his finger — as if the weight of responsibility of leading the 1.4-billion strong church had just sunk in.
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He turned his hand to look at the ring and seal and then clasped his hands in front of him in prayer.
Security was tight as civil protection crews in neon uniforms funneled pilgrims into quadrants in the piazza and up and down the boulevard that leads to it for the ceremony blending ancient ritual, evocative symbols and a dose of modern-day celebrity.
Australian Prime Minister Anthony Albanese attended. US Vice President JD Vance, one of the last foreign officials to see Pope Francis before he died, led the US delegation honouring the Chicago-born Leo after paying his respects at the Argentine pope's tomb upon arriving in Rome late on Saturday.
The theme of Leo's papacy
In his homily, Leo said he wanted to be a servant to the faithful through the two dimensions of the papacy, love and unity, so that the church could be a force for peace in the world.
"I would like that our first great desire be for a united church, a sign of unity and communion, which becomes a leaven for a reconciled world," he said. "In this our time, we still see too much discord, too many wounds caused by hatred, violence, prejudice, the fear of difference, and an economic paradigm that exploits the Earth's resources and marginalises the poorest."
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His call for unity was significant, given the polarisation in the Catholic Church in the United States and beyond.
Francis' radical 12-year pontificate, which emphasised care for the poor and marginalised and disdain for the capitalist economic system, often alienated conservatives and traditionalists. Leo's May 8 election, after a remarkably quick 24-hour conclave, has appeared at the outset to have pleased conservative Catholics who seem to appreciate his more disciplined, traditional style and Augustinian background, emphasising core truths of Catholic doctrine.
Tight security and protocol
Strict diplomatic protocol dictated the seating arrangements at his inaugural Mass, with both the United States and Peru getting front-row seats thanks to Leo's dual citizenship. Vance, a Catholic convert who tangled with Francis over the Trump administration's mass migrant deportation plans, is being joined by US Secretary of State Marco Rubio, who arrived in Rome ahead of time to try to advance Russia-Ukraine peace talks.
Peruvian President Dina Boluarte is one of around a dozen heads of state attending, as well as Ukrainian President Volodymyr Zelenskyy. Russia is being represented by the culture minister, Olga Liubimova.
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Diplomatic protocol also dictated the dress code: While most wore black, the handful of Catholic queens and princesses — Charlene of Monaco and Letizia of Spain among others — wore white in a special privilege allowed them. Three dozen of the world's other Christian churches sent their own delegations, the Jewish community had a 13-member delegation, half of them rabbis. Other representatives headed Buddhist, Muslim, Zoroastrian, Hindu, Sikh and Jain delegations.
Americans are rejoicing
US seminarian Ethan Menning, 21, from Omaha, Nebraska, wrapped himself in an American flag, purchased at a truck stop in Iowa, to celebrate.
"Rome always felt like home for a Catholic, but now coming here and seeing one of our own on the throne of Peter … it almost makes Jesus himself more accessible," he said.
Kalen Hill, a pilgrim from the US, got to St. Peter's soon after the gates opened at dawn Sunday morning and said he never expected an American would lead the 1.4-billion strong church.
"I would say all the Americans are emotional about it," he said. "It is really powerful for American Catholics who sometimes feel separated from the world church to be brought in and included in this community through Pope Leo."
Signs of Leo's priorities
The two symbols of the papacy handed to Leo were the pallium, and the fisherman's ring. The pallium, draped across his shoulders, symbolises the pastor carrying his flock as the pope carries the faithful. The ring, which becomes Leo's official seal, harks back to Jesus' call to the apostle Peter to cast his fishing nets.
The other symbolically important moment of the Mass was the representational rite of obedience to Leo: Whereas in the past all cardinals would vow obedience to the new pope, more recent papal installations involve representatives of cardinals, bishops, priests, deacons, nuns, married couples and young people participating in the rite.
In the days since his historic election, Leo has already sketched out some of his key priorities as pope. In his first foreign policy address, he said the Holy See's three pillars of diplomacy were peace, justice and truth. In his first major economics address, he emphasised the Catholic Church's social doctrine and the search for truth.
After the homily and at the end of the Mass, Leo will offer a final blessing and then go into the basilica to greet the heads of the more than 150 official delegations attending.
Security was tight, as it was for Francis' funeral on April 26, which drew an estimated 250,000 people. The piazza and main boulevard leading to it, and two nearby piazzas were set up with giant television screens, and dozens of portable toilets have been erected in a nearby park.
Gregory and Susan Hudak, who lived for 40 years in the Chicago area, found themselves in Rome after booking a trip in February, with just a faint hope of perhaps glimpsing the pope.
Seeing the popemobile pass by in front of them, with the Chicago-born Leo on board, was even better than watching Michael Jordan play, said Gary Hudak, a former altar boy wearing a Chicago Bears hat.
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"Originally, the only hope I had coming here was to see the inside of the Sistine Chapel," he said.
"I was glad the conclave was over, because I could get to see the inside of the Sistine Chapel. Seeing the pope was not scheduled, it was a long shot hope. And this was a treasure, simple as that."
