The King marked another milestone as he unveiled the first completed official portrait of himself since the coronation on Tuesday.
The painting depicts Charles wearing the uniform of the Welsh Guards, of which he was made Regimental Colonel in 1975 – a role which has since been passed on to the current Prince of Wales – Prince William.
The portrait, first commissioned in 2020 to celebrate Charles' 50 years as a member of The Drapers' Company in 2022, has been created by renowned artist, Jonathan Yeo.
The monarch, 75, was joined by his wife, Queen Camilla, 76, for the unveiling, alongside the artist, The Master of The Drapers' Company, Tom Harris and Past Master, William Charnley. Watch the King's reaction in the video below...
Jonathan, whose previous subjects include Sir David Attenborough and the late Queen Elizabeth II and Prince Philip, said: "It was a privilege and pleasure to have been commissioned by The Drapers' Company to paint this portrait of His Majesty The King, the first to be unveiled since his Coronation.
"When I started this project, His Majesty The King was still His Royal Highness The Prince of Wales, and much like the butterfly I've painted hovering over his shoulder, this portrait has evolved as the subject's role in our public life has transformed.
"I do my best to capture the life experiences etched into any individual sitter's face. In this case, my aim was also to make reference to the traditions of Royal portraiture but in a way that reflects a 21st Century Monarchy and, above all else, to communicate the subject's deep humanity.
"I'm unimaginably grateful for the opportunity to capture such an extraordinary and unique person, especially at the historic moment of becoming King."
How long did the portrait take?
Jonathan Yeo had four sittings with The King, beginning when His Majesty was Prince of Wales in June 2021 at Highgrove, and later at Clarence House. The last sitting took place in November 2023 at Clarence House.
He also worked from drawings and photography he took of His Majesty, allowing him to work on the portrait in his London studio between sittings.
Where will it be displayed?
The portrait will go on public display for a month at the Philip Mould Gallery in London, from 16 May until 14 June. Entry is free.
The artwork is expected to be displayed at Drapers' Hall from the end of August. Tours of the Hall can be booked by appointment, except from the end of July to mid-September when it is closed for maintenance and conservation.
The Drapers' Company dates back more than six centuries ago, when a group of merchants came together to promote their trade in woollen cloth in the City of London, with philanthropy as part of their plan.
Today, it has seven charitable trusts to help people in disadvantaged circumstances, with two-thirds of its support going to education and training. The remainder goes to the support of prisoners, homeless people; ex-service personnel; those with disabilities; and people in need of food, clothes and shelter.
Prince Albert, later George VI, became a Draper in 1919. Queen Elizabeth II became a Draper in 1947, joining the Court in 2017. King Charles III became a Freeman of the Drapers' Company in 1971, when the Company also provided offices for the newly formed Prince's Trust at Drapers' Hall.