It is run at Ascot over a distance of 1 mile 3 furlongs and 211 yards (2,406 metres), and it is scheduled to take place each year in July.
It is Britain's most prestigious open-age flat race, and its roll of honour features some of the most highly acclaimed horses of the sport's recent history.
The idea was conceived by Major John Crocker Bulteel, the Clerk of the Course at Ascot, who wanted to create an important international race over one and a half miles for horses aged three or older.
During the early part of its history the King George VI and Queen Elizabeth Stakes was not commercially sponsored.
It became known as the King George VI and Queen Elizabeth Diamond Stakes, and De Beers continued to back the event until 2006.