Cardinal Robert Francis Prevost has been elected the 267th pope – and the first from the US – after he was chosen in a centuries-old ritual.
The cardinal, 69, has taken the name Pope Leo XIV. He was greeted by cheering crowds as he made his first appearance on the balcony of St Peter's Basilica.
"Greetings, brothers and sisters," he told them in his first address as leader of the world's 1.4 billion Roman Catholics. "May peace be with you." He called worshippers to pray for the late Pope Francis, who died on April 21.
He thanked cardinals who elected him as Bishop of Rome and the spiritual successor to Saint Peter, the first pope. “We have to be a church that works together to build bridges," he said.
US President Donald Trump called the election of the first American pope a "great honour for our country". He said he looked forward to meeting Pope Leo in what would be a "very meaningful moment".
UAE President Sheikh Mohamed wished Pope Leo success in "continuing to promote mutual understanding, peace and harmony throughout the world", as congratulations poured in from leaders including French President Emmanuel Macron and Russia's President Vladimir Putin.
Named a cardinal by Pope Francis in 2023, the new pontiff was born in Chicago in 1955. Having worked as a missionary in Peru, he later served as a bishop there.
In his first address he spoke in Italian and then switched to Spanish, recalling his years in Peru.
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Observers regard a pope's choice of name as an early clue to their intentions. Pope Leo XIII, the last with that name, served from 1878 to 1903 and helped to set up the Catholic University of America in Washington.
Pope Francis, who died at 88, was seen as a moderniser and a champion of the unfortunate, including refugees and those affected by the war in Gaza. A former archbishop in Argentina, he was the first pope from the Americas.
Pope Leo XIV elected - in pictures
White smoke
As is tradition, the announcement that the 133 cardinals making up the conclave had come to a decision was made using white smoke, which rose from a specially built chimney of the Sistine Chapel in the Vatican.
Cheers went up as the white smoke emerged at 6.07pm local time, accompanied by the ringing of Vatican bells.
It fell to French Cardinal Dominique Mamberti to deliver the words "habemus papam" – Latin for "we have a pope" – to those gathered in the piazza.
The conclave began on Wednesday when cardinals entered the Sistine Chapel two by two, chanting the meditative Litany of the Saints as Swiss Guards stood at attention. The hymn, and the one that followed, implores the saints and the holy spirit to help the cardinals find a new pontiff.
Coming from 70 countries, the cardinals were sequestered from the outside world. Their mobile phones were surrendered and airwaves around the Vatican jammed to prevent all communications until they reached a two-thirds majority decision.
Italian clergymen had held a firm grip on the papacy for almost 400 years, until Pope John Paul II became the first Polish pontiff in 1978. Since then, Italian contenders have been overlooked in favour of the German Pope Benedict XVI in 2005, the Argentinian Pope Francis in 2013, and now Pope Leo XIV.
More than 80 of the cardinals in this year's conclave were appointed by Pope Francis, who died last month after a 12-year papacy.
