Prince Charles was promoted by Queen Elizabeth to the highest ranks in all three military services on Saturday.
The queen appointed her eldest son to the honorary ranks of field marshal, admiral of the fleet and marshal of the Royal Air Force.
Charles, 63, served in the Royal Navy and the RAF throughout the 1970s.
Only two other members of the royal family hold similarly senior honorary rank: Prince Philip -- in all three services -- and Prince Edward, the Duke of Kent, who is a field marshal.
Charles's sons are both helicopter pilots -- Prince William in a search and rescue role with the RAF and Prince Harry on attack choppers with the Army Air Corps.
Meanwhile General Charles Guthrie, who was chief of the defence staff between 1997 and 2001, has also been awarded the honorary rank of field marshal.