On Thursday, May 8, the Vatican announced that Cardinal Robert Prevost, has been elected as the new pope, taking the name Leo XIV.

This is the first time in 150 years that the name Leo was chosen by a pope, despite it being one of the most popular papal names.

According to the Catholic Encyclopedia, Leo is the fourth most popular papal name and it has been used by 14 Popes. The Most Popular is John that has been chosen 21 times, followed by Gregory 16, Benedict 15, Leo and Clement 14 times.

The last Pope Leo was Leo XIII, who was born in French-occupied Rome in 1810. He served as pope from 1878 until his death in 1903, making his 25-year papacy the fourth longest in the church’s history.

Leo XIII is remembered as a pope of Catholic social teaching. He wrote a famous open letter to all Catholics in 1891, called “Rerum Novarum” (“Of Revolutionary Change”). The pamphlet reflected on the destruction wrought by the Industrial Revolution on the lives of workers.

In a press briefing Thursday after the conclave, Vatican spokesperson Matteo Bruni said the choice of name “is a clear reference to the modern social doctrine of the Church, which began with Rerum Novarum.”

Bruni said the name Leo was a deliberate reference to “men, women, their work, and workers in an age of artificial intelligence,” seeming to link the pace of technological change of the current era to that of the nineteenth century.

Born on 2 March 1810 in the Lazio region, Vincenzo Gioacchino Pecci ( Pope Leo XIII) was the sixth of seven children. He was ordained a priest on 31 December 1837 and was elected as Pope Leo XIII in February 1878 after a three-day conclave in which he gained 44 out of 61 votes.

Pope Leo XIII was the earliest-born person ever recorded on photographic film. Born in 1810, he was filmed in 1896, making him the first pope to appear on camera. The color footage, captured in the Vatican gardens, provides a rare glimpse into the life of a 19th-century pontiff.

He died of pneumonia in Rome’s Apostolic Palace in July 20, 1903 at 93 years old.

The first Pope Leo, who served in the fifth century, is known as “Leo the Great,” and is remembered for persuading Attila the Hun to halt his invasion and spare the Roman Empire from destruction.

The name Leo derives from the Latin for “lion,” suggesting strength and courage.

Some biblical names that haven’t been used by a pope are Joseph, James and Andrew.

Popes also have not chosen the name Peter, out of respect for St. Peter, a disciple of Jesus who is recognized as the first pope of the Catholic Church.