The clues were there when Leo spoke to the world from the balcony of St Peter’s Basilica more than a year ago.

“Peace be with you,” he said, emerging shortly after smoke from the Sistine Chapel indicated a successor to Pope Francis had been chosen. He said the church must “be close, above all, to those who are suffering”.

In the US, where an estimated 20 per cent of the population identifies as Catholic, there was widespread excitement. While Leo, 70, worked as a missionary in Latin America, he had been born plain Robert Francis Prevost, in Chicago. His father served in the navy and his mother was a school administrator. He had two brothers.

The media quickly filled with stories about his love for the White Sox baseball team and how he’d “played priest” as a child and distributed chocolates in place of consecrated wafers. “We knew from the start, he’s going to go into the priesthood,” one brother, Louis, told CNN. One television channel tracked down his favourite pizza place, Aurelio’s.

Leo’s roots in the American heartland were extremely significant. While his predecessor, Francis, born in Argentina, could claim to be the first pope from “the Americas”, he most frequently spoke in Italian or Spanish. By contrast, while Leo also speaks Spanish and Italian, he also converses powerfully in English, meaning his comments are easily understood in his home country.