Charles, the Prince of Wales, becomes the UK's King at the age 73.
The Queen had been being treated by physicians at her sprawling Balmoral estate in Aberdeenshire, Scotland. Her death comes after a seven-decade tenure marked by consistency and stability.
"The Queen died peacefully at Balmoral this afternoon," a statement by Buckingham Palace released around 1:35 p.m. Eastern time Thursday, Sept. 8 succinctly stated. "The King and the Queen Consort (Camilla, Duchess of Cornwall) will remain at Balmoral this evening and will return to London tomorrow."
Queen Elizabeth's death comes just two days after she formally welcomed newly-named prime minister Liz Truss at Balmoral.
Truss is the queen's 15th prime minister. Her first was Winston Churchill, who was born in 1874.
Prince William, age 40, one of Charles' two sons, is now second in line to the thrown behind King Charles.
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