Vatican: In a landmark ceremony at the Vatican on Sunday, Pope Leo declared Carlo Acutis, a teenage coder known as “God’s influencer,” the first saint representing the millennial generation.

Thousands of young worshippers from across the globe gathered in St. Peter’s Square to witness the canonisation.

Born in London in 1991 and later raised in Italy's Milan, Acutis was baptised at Our Lady of Dolours Church, where an old confessional has since been turned into a shrine. He died in October 2006 from leukaemia at the age of 15.

Despite his short life, Acutis earned international recognition for designing websites that documented miracles to spread Catholic teaching, earning him the nickname “God’s influencer.”

His devotion and digital evangelism continue to inspire Catholic youth, who now revere him alongside revered figures like Mother Teresa and St. Francis of Assisi.

On Sunday, Acutis was canonised together with Pier Giorgio Frassati, an Italian remembered for his charitable work before dying of polio in the 1920s.

Speaking to the crowds, Pope Leo — the first American-born pontiff — called both men “shining examples of holiness and service to others.”

Canonisation formally acknowledges that an individual lived a holy life and is now in heaven.

The canonisation of Acutis had initially been scheduled for April but was delayed following the death of Pope Francis on April 21.

This marked Pope Leo’s first canonisation ceremony since his ascension.

Following the announcement, young Catholics at the Vatican expressed joy, saying they drew inspiration from Acutis’s journey.

His body was transferred to Assisi, the hometown of St. Francis, in keeping with his last wishes.

The town has since become a major pilgrimage site, with Carlo’s preserved body displayed in a wax casing.

More than a million people are believed to have already visited Assisi, underlining his continuing influence on the global Catholic community, according to media reports.