Queen Elizabeth II, the United Kingdom's longest-serving monarch, has died at Balmoral in Scotland aged 96, after reigning for 70 years.
With her death, her eldest son Charles, the former Prince of Wales, will lead the country in mourning as the new King and head of state for 14 Commonwealth realms.
In a statement, Buckingham Palace said, "The Queen died peacefully at Balmoral this afternoon. The King and the Queen Consort will remain at Balmoral this evening and will return to London tomorrow."
Her family gathered at her Scottish estate after concerns grew about her health earlier today. All the Queen's children travelled to Balmoral, near Aberdeen, after doctors placed the Queen under medical supervision.
Her grandson, Prince William, is also there, with his brother, Prince Harry, on his way.
At Buckingham Palace in London, crowds awaiting updates on the Queen's condition began crying as they heard of her death. The Union flag on top of the palace was lowered to half-mast at 18:30 BST.
The Queen came to the throne in 1952 and witnessed enormous social change. Her tenure as head of state spanned post-war austerity, the transition from empire to Commonwealth, the end of the Cold War and the UK's entry into - and withdrawal from - the European Union.
Her reign spanned 15 prime ministers starting with Winston Churchill, born in 1874, and including Liz Truss, born 101 years later in 1975, and appointed by the Queen earlier this week.
The Queen was born Elizabeth Alexandra Mary Windsor, in Mayfair, London, on April 21, 1926. She was married to Philip, Prince of Greece on November 20, 1947, with the prince taking the title of Duke of Edinburgh. After 74 years of marriage, he died in 2021, aged 99.