Over her 60-year reign, there have been no fewer than 12 prime ministers, who have all sought her advice on matters, traditionally on a weekly basis.
The HuffPost looks back over the last 60 years and the prime ministers who have served under her.
Winston Churchill was initailly sceptical of the new young Queen, calling her "just a girl".
The Queen and Eden disagreed heavily over the Suez crisis calling him 'mad' over his decision to intervene militarily
Macmillan was "astonished by her grasp of detail" but also noted that she was irritated when treated like a woman
A shared love of dogs allowed the two to develop a close relationship
Wilson described his visits with the Queen as "going to see mother".
Edward Heath, far right, clashed repeatedly with the Queen. A former courtier recalled how that Queen was never comfortable with him. At an event in 2002 at Buckingham Palace that the Queen held to honour all of her surviving Prime Ministers, Heath dozed off.
Callaghan was very secretive of his meetings with the Queen and it is claimed that the two indulged in 'flirtatious banter'
The Queen's relationship with Thatcher was tense and the Queen allegedly referred to her as "that lady"
Major appreciated the ability to talk to the Queen about anything, even things he did not feel comfortable talking to his ministers about.
The Queen was devastated when Blair decommissioned the Royal Yacht Britannia. She was also very critical of his close relationship with George W Bush
Brown took great care to follow traditional protocol around the Queen
Cameron has recently praised the value of his weekly meetings with the Queen saying that he appreciates her views which are capable of seeing through the politics.