King Charles III on Thursday joined Pope Leo XIV for prayers at the Sistine Chapel during a visit to Vatican City, making history as the first UK monarch to participate in a Catholic Church service since King Henry VIII broke away from papal authority in the sixteenth century.

The 76-year-old monarch is on a two-day state visit to the Holy See, as the central governing body of the Vatican-based Roman Catholic Church in Italy is known, with wife Queen Camilla. The special service commemorates the Catholic Church’s jubilee year and is designed to boost ties between the Vatican and the Anglican Church, of which the British monarch is the Supreme Governor.

“Their Majesties will visit the Holy See to celebrate the 2025 Papal Jubilee and the warm ecumenical relationship between the Church of England, of which His Majesty is Supreme Governor, and the Roman Catholic Church," Buckingham Palace said in a statement.

The ecumenical service, representing different Christian Churches, at the Sistine Chapel was themed around "care for creation" and followed by a private meeting centred around sustainability.

“The King and Queen, accompanied by Pope Leo, have attended a special service in the Sistine Chapel, marking the joining of hands between the Catholic Church and Church of England, in a celebration of ecumenism,” the palace said in a social media post soon after.

In a departure from tradition, the palace had allowed the King to be filmed in prayer seated in a chair decorated with the Charles' coat of arms and the ecumenical motto "ut unum sint" - Latin for "that they may be one".

The chair was crafted specifically for the occasion and will remain at the Church for use by the King as the new "Royal Confrater" of the basilica and his successors. King Charles also received a Papal knighthood from Pope Leo.

In return, the Pope was made "Papal Confrater" of St. George's Chapel at Windsor Castle and conferred a Knight Grand Cross of the Order of the Bath.

Earlier, the two leaders exchanged official gifts in the Pope’s library – the Pope presenting the King with a scale version of a mosaic from the Norman Cathedral of Cefalu in Sicily.

The King gifted the Pope a silver photograph of himself and his wife and an icon of St. Edward the Confessor, an Anglo-Saxon king of England and one of only a handful of English royal saints.

The leaders also exchanged gifts of trees to be planted, symbolising their joint commitment to the environment. King Charles and Queen Camilla last visited the Vatican earlier this year, when they had a private meeting with Pope Francis shortly before he died, during a state visit to the Republic of Italy.

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