King Charles III is the military's Commander-in-Chief.
He has always maintained a close relationship with the Armed Forces and served in the both Royal Navy and Royal Air Force.
Here is a look at his time serving in the military.
King Charles III's military career
On 8 March 1971, the King – then known as Prince Charles – flew himself to RAF Cranwell in Lincolnshire to train as a jet pilot.
He had been given flying instruction from the Royal Air Force during his second year at Cambridge University.
Later that year, after passing out at RAF Cranwell, he embarked on a career in the Royal Navy, following in the footsteps of his father, grandfather and both great-grandfathers.
Following his six-week course at Britannia Royal Naval College Dartmouth, he spent time serving on the guided missile destroyer HMS Norfolk and two frigates – HMS Minerva and HMS Jupiter.
1974 saw the future King qualify as a helicopter pilot and he flew Wessex helicopters with 845 Naval Air Squadron from the commando aircraft carrier HMS Hermes.
In February 1976, the then-Prince of Wales took command of coastal minehunter HMS Bronington, before ending his Royal Navy service nine months later.
Despite leaving the military, the King has continued to work closely with the Armed Forces and in 2012, Queen Elizabeth II awarded him the highest rank in all three services – Field Marshal, Admiral of the Fleet and Marshal of the Royal Air Force.
He has been the Commander-in-Chief of the UK Armed Forces since the death of his mother, Queen Elizabeth II, in September 2022.
A month later, the King replaced the Duke of Sussex as Captain General of the Royal Marines - the ceremonial head of the corps.