Why does the Queen have two birthdays — and what is she doing this year?
Queen Elizabeth II is the oldest monarch in British history.
Elizabeth was born on April 21, 1926 in London. She is owned here by her mother, also named Elizabeth. His father would later become King George VI.
Princess Elizabeth poses for a photo at her London home in 1928.
Princess Elizabeth is seen with her uncle Edward, Prince of Wales, during a visit to Balmoral, Scotland, in September 1933. He became King Edward VIII in 1936. But when he abdicated later that year, Elizabeth’s father became king and she became presumptive heiress.
From left to right, Princess Elizabeth, King George VI, Queen Elizabeth and Princess Margaret greet the crowd from the balcony of Buckingham Palace on June 22, 1939.
Elizabeth rides a horse in Windsor, England in 1940. Her love for horses is well documented.
Elizabeth, 14, right, sits next to her sister for a radio show on October 13, 1940. On the show, the first, she said that the children of England were full of cheerfulness and courage.
Princess Elizabeth shakes hands with a Grenadier Guard officer on May 29, 1942. King George VI made Elizabeth an honorary colonel of the Royal Army regiment.
Elizabeth, on the right, and Princess Margaret wear summer dresses around 1942. Margaret is Elizabeth’s only sister.
With the Drakensberg Mountains behind her, Princess Elizabeth sits in Natal National Park in South Africa on April 21, 1947. It was her 21st birthday.
On November 20, 1947, Elizabeth married Prince Philip, a lieutenant in the British Navy born into the royal families of Greece and Denmark. After becoming a British citizen and renouncing his Greek title, Philip became His Royal Highness Prince Philip, Duke of Edinburgh. His wife became the Duchess of Edinburgh.
Princess Elizabeth arrives at a state banquet in London in March 1950.
Elizabeth ascended the throne in February 1952, when her father died of lung cancer at the age of 56. Here, she walks to the altar during her coronation ceremony on June 2, 1953.
Queen Elizabeth II is pictured on the balcony of the Melbourne government residence during her Australian tour in March 1954.
From left to right, Princess Margaret, Queen Elizabeth II and the Queen Mother visit the Epsom Downs racetrack in June 1958.
The Queen holds her son Prince Andrew while her sister, Princess Anne, watches during a family vacation at Balmoral Castle in Scotland in September 1960. The Queen has four children, including sons Charles and Edward.
Queen Elizabeth II is seen during the opening of Parliament in April 1966.
Queen Elizabeth II with her eldest son, Prince Charles, in 1969. Charles is then in line for the throne.
Prince Charles adjusts his crown during his investiture ceremony as Prince of Wales in 1969.
The Queen and Prince Philip undulate from an airplane ramp shortly before taking off from Tokyo in May 1975.
The Queen takes a portrait at Windsor Castle for her 50th birthday on April 21, 1976.
The Queen meets the crowd during her royal tour of New Zealand in 1977.
Elizabeth walks with some of her corgis at the Windsor Horse Trials in May 1980.
The Queen stands next to Prince Charles as he kisses his new wife, Princess Diana, on July 29, 1981.
Elizabeth takes photos of her husband at a horse show in Windsor in May 1982.
Elizabeth drives her Land Rover at the Royal Windsor Horse Show in May 1992.
At Buckingham Palace, the Queen and Prince Philip see the floral tributes to Princess Diana after her tragic death in 1997.
The Queen addresses the nation the night before the funeral of Princess Diana in 1997.
Prince Charles returns to his mother after the marriage of Camilla, Duchess of Cornwall, in April 2005.
The Queen, second on the right, welcomes a crowd from the balcony of Buckingham Palace on April 29, 2011. Her grandson, Prince William, third on the left, had just married Catherine Middleton.
The queen’s signature is visible in the guest book of Aras An Uachtarain, the official residence of the Irish president in Dublin in May 2011.
Madame Tussauds London reveals a wax figure of the queen in May 2012.
Prince Charles kisses his mother’s hand on stage as singer Paul McCartney, on the far right, watches the Diamond Jubilee concert in June 2012. Diamond Jubilee celebrations marked Elizabeth’s 60th birthday as Queen.
The Queen visits the Foreign and Commonwealth Office in London in December 2012.
A boy in Belfast, Northern Ireland, takes a selfie in front of the Queen in June 2014.
The Queen enters the Great Hall of Edinburgh Castle after attending a memorial service for the Scottish National War Memorial in July 2014.
The Queen waits to deliver her speech at the opening of Parliament in May 2015.
Elizabeth listens to her great grandson, Prince George, outside a church where George’s sister, Charlotte, was baptized in July 2015. George and Charlotte are the children of Prince William, on the left, and Duchess Catherine.
The Queen and Prince Philip greet guests in London who attended the celebrations of his 90th birthday in 2016.
Elizabeth talks to Evie Mills, 14, at a hospital in Manchester, England, in May 2017. Evie was injured in a bomb attack that took place while people were leaving a Ariana Grande concert.
The Queen sits at a desk at Buckingham Palace after recording her broadcast of Christmas Day in 2017.
The Queen arrives for the wedding of her grandson Prince Harry and Meghan Markle in May 2018.
The Queen laughs with Meghan, Duchess of Sussex, at a bridge opening ceremony in Halton, England, in June 2018. It was Meghan’s first royal outing without her husband, Prince Harry, by her side .