On Sept. 7, 2025 in St. Peter’s Square, Vatican City, Pope Leo canonized Carlo Acutis — a British-born Italian who died of leukaemia in 2006 at age 15 — making him the first recorded millennial to be declared a Catholic saint; the Mass was attended by an estimated 70,000 mainly young worshippers from dozens of countries.
Key Takeaways
- Carlo Acutis, who died in 2006 aged 15, was declared a saint on Sept. 7, 2025 in a Vatican ceremony led by Pope Leo.
- About 70,000 mostly young people from many countries attended the canonization in St. Peter’s Square.
- Acutis was known for using computer coding and websites to promote his Catholic faith.
- Pope Leo, the first U.S.-born pontiff, canonized Acutis alongside Pier Giorgio Frassati, who died of polio in the 1920s.
- The event had been postponed from April after the death of Pope Francis; it is Pope Leo’s first canonization since his election in May.
- Acutis’ remains were moved to Assisi in line with his wishes and remain a daily pilgrimage site, where he is displayed wearing casual clothing with a wax likeness.
Verified Facts
Carlo Acutis, born in Britain to Italian parents, died in 2006 at age 15 from leukaemia. He built websites and used digital tools to document Eucharistic miracles and to spread Catholic teaching, gaining a notable following among young Catholics.
Pope Leo led the canonization Mass in St. Peter’s Square on Sept. 7, 2025. The ceremony also declared Pier Giorgio Frassati, a young Italian known for charity work who died of polio in the 1920s, a saint.
Organizers and Vatican officials estimated roughly 70,000 attendees, many of them youth who travelled from across Europe and beyond. The crowd extended beyond the square along the main avenue into Rome.
Acutis’ cause for sainthood followed the Church’s formal procedures. His body was transferred to a church in Assisi, where a wax effigy clothes the body in the casual attire he liked; the site receives thousands of visitors daily.
Context & Impact
The canonization is significant for Catholic outreach to younger generations: Acutis’ use of technology to share faith stories presents a contemporary model of holiness the Church highlights to connect with digital-native Catholics.
Pope Leo framed both new saints as examples for young people to devote their lives to service and spiritual growth. The spectacle of a large youth turnout may encourage further pastoral initiatives aimed at young Catholics worldwide.
For the Vatican, the event also marked continuity amid transition: originally scheduled for April, the ceremony was postponed after Pope Francis’ death; it is the first canonization presided over by Pope Leo since his election in May 2025.
Official Statements
“All of you, all of us together, are called to be saints,” Pope Leo told the assembled crowd, urging young people not to squander their lives but to direct them upward.
Pope Leo, Sept. 7, 2025
Unconfirmed
- Precise breakdown of international delegations and origin countries for the 70,000 attendees has not been published by the Vatican.
- Public details of the specific miracles cited in Acutis’ canonization paperwork were not enumerated in ceremony summaries available at press time.
Bottom Line
Carlo Acutis’ canonization on Sept. 7, 2025 represents a symbolic moment for the Catholic Church as it highlights a young, tech-savvy model of sanctity. The ceremony, attended by tens of thousands of youths, may shape future outreach and the Church’s engagement with digital culture.