Queen Elizabeth died at the age of 96 on Thursday, 8 September.
Following recent struggles with her health that saw her cancel various engagements, Buckingham Palace announced: "The Queen died peacefully at Balmoral this afternoon."
The queen's four children, including heir apparent, Prince Charles, were by her side when she died.
Charles, next in line to the throne, followed by son Prince William and then Prince George, succeeds the queen.
The queen said earlier this year, ahead of her Platinum Jubilee – a record-breaking 70 years on the throne – she hoped the British people would give Charles and Camilla "the same support that you have given me".
"It is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service," she said of Charles' second wife, after that of Princess Diana, Camilla Parker Bowles, Duchess of Cornwall.
At the time, the statement ended "years of controversy and confusion" caused, for the most part, by Camilla's role in the heir apparent's split from Princess Diana.
While Camilla will likely be referred to as "Queen Camilla" – contentious in itself following the press release in 2005 upon Charles' marriage to Camilla indicating "Mrs Parker Bowles should use the title HRH The Princess Consort when The Prince of Wales accedes to The Throne" – "Queen Consort" is the traditional title for the wife of the reigning monarch.
She will, therefore, not use the title of "Queen" in the same way Queen Elizabeth II has, but as wife of King Charles III.
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