Have you ever wondered why the birthday of Queen Elizabeth II, born on 21 April 1926, is also celebrated in June? Queen Elizabeth’s birthday is traditionally celebrated twice a year: the first on her actual date of birth, April 21, and the second (the official one) in June.
The tradition of celebrating a birthday twice, with one public and one private celebration, began with King Edward VII, born on November 9, 1841. The official date of his birth was moved to spring (May or June, depending on the year). so as to have a better chance of good weather for the celebration ceremony.
Elizabeth’s institutional birthday, on the other hand, is celebrated with the traditional Trooping of the Color parade in central London. Then the queen, now without the prince consort Philip (who died on April 9, 2021), parades in a carriage through the streets of the city, greeting the subjects and witnesses the firing of 41 cannon shots by the armed forces.
Source: Vanity Fair