Her Majesty, who is patron of the British Olympic Association (BOA), will be the first head of state to open a summer Olympic Games on two separate occasions.
In 1976, she performed the opening of the Montreal Games, and unusually made the declaration in French to reflect the heritage of Quebec. She had been invited to do so on the advice of the Canadian Prime Minister, Pierre Trudeau. For the Queen, there was another reason for this to be memorable. As her daughter Princess Anne, an eventing competitor, took part in the march past as part of the Great Britain team. In 1992, King Juan Carlos of Spain had a similar experience and reviewed a parade that included his son Prince Felipe.
In 1956, The Queen had attended the opening of the Olympic equestrian events held in Stockholm because of difficulties with quarantine regulations in Melbourne. She watched her own horse Countryman ridden by Bertie Hill (pictured), play his part in Great Britain's gold medal winning three day event team. They were received on the Royal Yacht Britannia before leaving Stockholm.
That November, Prince Philip, dressed in full naval uniform, opened the main part of the Games before a packed Melbourne Cricket Ground. On that occasion he represented the Queen.
In 1948, then still Princess Elizabeth, she had been an expectant mother at the time of the London Games. A matter of days before the opening she had been presented with the Lychnos or lamp used at the lighting of the Olympic flame. This was a gift from the Hellenic Olympic Committee. Much later she used a 1948 Olympic torch at the 1977 silver jubilee celebrations to light the first of a chain of beacons.
At the opening ceremony on a scorching day, her father George VI made the opening declaration and Prince Philip later acted as the starter for the cycling road race in Windsor Great Park, offered as a venue by the King.
The Queen's own involvement this year in both Olympic and Paralympic ceremonies sets the seal on over a century or Royal involvement with the Games.
When he revived the Olympic Games, Baron Pierre de Coubertin solicited the support of the Prince of Wales at the establishment of the International Olympic Committee in 1894.
Within seven years, the Prince had become King Edward VII, and in 1908, he performed the ceremonial opening of the Games.
After the dramatic conclusion to the marathon when the Italian Dorando was disqualified, Queen Alexandra (pictured) presented the runner with a special cup by way of consolation.
After the first world war, the Queen's uncle David, Prince of Wales (later Edward VIII) was an enthusiastic supporter of the Games and travelled with Prince Henry to the 1924 "Chariots of Fire" Olympics in Paris. He led the British team to the Arc de Triomphe and laid a wreath at the tomb of the unknown soldier.
He was guest of honour at a BOA banquet for 200, including Marshall Foch. At one point, leapt to his feet and handed glasses of champagne to the pipers who were serenading the guests.
At the opening ceremony in the Stade de Colombes,he sat alongside Baron Pierre de Coubertin and the French President Gaston Domergue.
Coubertin later recalled how "one afternoon the Prince looked at his watch and asked anxiously, 'I would very much like to go and play polo in the Bois de Boulogne but if there is an Englishman due to compete I cannot go'."
There was, and the Prince stayed in his seat " without the slightest sign of annoyance."
At least the events in 1924 were all complete by early evening. By the time the Queen is invited to speak on July 27, it will be almost midnight.
Philip Barker, a freelance journalist, has been on the editorial team of the Journal of Olympic History and is credited with having transformed the publication into one of the most respected historical publications on the history of the Olympic Games. He is also an expert on Olympic music, a field which is not generally well known