King Charles has become the new captain general of the Royal Marines, a job that has been vacant since Prince Harry quit royal life.
The announcement comes as the the Royal Marines celebrates its 358th birthday today.
Prince Harry was reportedly saddenned and "devastated" at stepping down from the role in March 2020 following Megxit, a post he had held since 2017.
"I feel I’m letting people down, but I had no choice," he told the Commandant General Royal Marines, Matthew Holmes, and other senior figures at the Mountbatten Festival of Music two years ago.
Following his appointment today, the King said in a personal message: "It is the greatest possible pleasure to assume the role of your Captain General.
"I am exceptionally proud to follow in the footsteps of so many members of my family over the last three and a half centuries, all of whom held the role with a deep sense of admiration.
"The Royal Marines have a distinguished and unparalleled history, both on land and at sea. I draw immense inspiration from your courage, determination, self-discipline and a remarkable capacity to endure in the most extreme environments."
He added: "I feel greatly honoured to become part of the Corps Family and very much look forward to meeting many of you in the near future. In the meantime, this comes with my heartfelt and special wishes for a very happy 358th birthday.
"Per Mare, Per Terram."
Today marks the 358th anniversary of the founding of the Corps of Royal Marines, which were formed on October 28, 1664 during the reign of King Charles II.
King Charles III, meanwhile, previously trained and served alongside the Royal Marines during his Naval career.
As Prince of Wales he underwent training at the Commando Training Centre Royal Marines (CTCRM) in Lympstone, Devon, in order to qualify as a helicopter pilot.
His Majesty also later served alongside Royal Marines on board HMS Hermes, as part of 845 Naval Air Squadron, completing military exercises in the Western Atlantic and the West Indies.
The King holds the honorary rank of Admiral of the Fleet in the Royal Navy.
The role of the ceremonial head of the Royal Marines has historically been held by the Monarch, including The King’s grandfather and great-grandfather, with King George V first assuming the appointment in 1901.
The motto of the Royal Marines, ‘Per Mare, Per Terram’, means ‘By Sea, By Land’ in Latin, reflecting their amphibious expertise.
While qualifying as a helicopter pilot in 1974, the King undertook commando training with the Royal Marines at Lympstone in Devon.
His Majesty then joined 845 Naval Air Squadron, serving alongside a detachment of Royal Marines on board HMS Hermes.
On February 9, 1976, the then-Prince took command of the coastal minehunter HMS Bronington for his last nine months in the Royal Navy.
The Royal Marines are currently operating in the Mediterranean, forging closer bonds with NATO allies and partners.
Commandos are also deployed with HMS Montrose in the Middle East to disrupt the global drugs trade, and will soon be operating in Oman.
Royal Marines will also be undertaking their traditional mountain training in Scotland as they prepare to spend the winter in the Arctic Circle in Northern Norway.
It had previously been thought that Prince William would take on the vacant role, with Princess Anne also mooted to become the first woman to occupy the post.