Pope Leo XIV will on Friday celebrate his first mass as Pope after his election as the first man from North America to lead the world's 1.4 billion Catholics.
The 69-year-old former cardinal, Robert Francis Prevost, will gather in the Sistine Chapel with the 132 cardinals who elected him on Thursday evening.
Messages of support have poured in from world leaders.
"Congratulations to Cardinal Robert Francis Prevost," said US President Donald Trump in a post on Truth Social.
"It is such an honor to realise that he is the first American Pope. What excitement, and what a Great Honor for our Country. I look forward to meeting Pope Leo XIV. It will be a very meaningful moment!"
Australian Prime Minister Anthony Albanese called it a momentous day for Catholics around the world.
"My government looks forward to continuing Australia's strong relationship with the Holy See under Pope Leo XIV's pontificate," he said.
He also invited the pope to visit Australia for the 2028 International Eucharist Congress. Around six million Catholics live in Australia.
Prevost had been seen as a top contender for the papacy after Pope Francis appointed him to lead the Vatican’s Dicastery for Bishops, which oversees bishop nominations globally.
In his first public remarks as pontiff, delivered in near-perfect Italian, Pope Leo said: “Together, we must try to find out how to be a missionary church, a church that builds bridges, establishes dialogue, that’s always open to receive — like on this piazza with open arms — to be able to receive everybody that needs our charity, our presence, dialogue and love.”
Unwritten taboo
There has long been an unwritten rule against electing an American pope, due to the United States’ role as a global superpower.
But Prevost’s long connection to Peru — where he served first as a missionary, then as a bishop — appears to have reassured many within the church.
Peruvian President Dina Boluarte saluted the choice, describing Prevost as a Peruvian by choice and conviction.
"He chose to be one of us, to live among us and to carry in his heart the faith, culture and dreams of this country,” she said on social media.
The last pope to take the name Leo was Leo XIII, an Italian who led the church from 1878 to 1903. He is remembered for softening the church’s approach to science and politics, and for laying the foundations of Catholic social teaching.
His most famous encyclical, Rerum Novarum, was issued in 1891. It dealt with workers’ rights and capitalism during the rise of industrialisation. The Vatican has referenced this document when explaining the new pope’s choice of name.
Vatican watchers said Prevost’s decision to name himself Leo was particularly significant given the previous Leo’s legacy of social justice and reform, suggesting continuity with some of Pope Francis’s chief concerns.
Specifically, Leo cited one of Francis’s key priorities of making the Catholic Church more attentive to lay people and inclusive.
“He is continuing a lot of Francis’s ministry,’’ said Natalia Imperatori-Lee, the chair of religious studies at Manhattan University in the Bronx.
But she also said his election could send a message to the American church, which has been badly divided between conservatives and progressives.
“I think it is going to be exciting to see a different kind of American Catholicism in Rome,’’ Imperatori-Lee said.
