The Queen sat on the throne longer than any other monarch in British history and right up until her tragic passing on Thursday 8 September 2022, she kept a promise that she made on her 21st birthday 50 years ago.
MORE: The Queen's 15 Prime Ministers: From Winston Churchill to new leader Liz Truss
In a speech broadcast on the radio from Cape Town when the then-princess was on a tour of South Africa with her parents and younger sister, the late monarch vowed to dedicate her whole life to the service of the Commonwealth.
WATCH: The Queen’s 70-year reign in 70 pictures
She said: "I declare before you all that my whole life whether it be long or short shall be devoted to your service and the service of our great imperial family to which we all belong."
The Queen passed away at the age of 96 at Balmoral Castle.
Her death was announced in a statement from Buckingham Palace that read: "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."
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Her sad passing comes the same year she celebrated a remarkable 70 years on the throne, over which she saw 15 Prime Ministers and countless world leaders come into power.
The Queen's coronation took place on 2 June 1953
Tributes have poured in from across the globe in honour of the beloved monarch. In a statement, a heartbroken King Charles said: "The death of my beloved Mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family.
"We mourn profoundly the passing of a cherished Sovereign and a much-loved Mother.
"I know her loss will be deeply felt throughout the country, the Realms and the Commonwealth, and by countless people around the world.
"During this period of mourning and change, my family and I will be comforted and sustained by our knowledge of the respect and deep affection in which The Queen was so widely held."
King Charles paid tribute to his late mother in a moving statement
Meanwhile, Prince William - the new Prince of Wales - said: "On Thursday, the world lost an extraordinary leader, whose commitment to the country, the Realms and the Commonwealth was absolute. So much will be said in the days ahead about the meaning of her historic reign.
"I, however, have lost a grandmother. And while I will grieve her loss, I also feel incredibly grateful. I have had the benefit of The Queen's wisdom and reassurance into my fifth decade.
"My wife has had 20 years of her guidance and support. My three children have got to spend holidays with her and create memories that will last their whole lives.
"She was by my side at my happiest moments. And she was by my side during the saddest days of my life. I knew this day would come, but it will be some time before the reality of life without Grannie will truly feel real.
The Prince and Princess of Wales viewing floral tributes to the Queen in Windsor
"I thank her for the kindness she showed my family and me. And I thank her on behalf of my generation for providing an example of service and dignity in public life that was from a different age, but always relevant to us all.
"My grandmother famously said that grief was the price we pay for love. All of the sadness we will feel in the coming weeks will be testament to the love we felt for our extraordinary Queen.
"I will honour her memory by supporting my father, the King, in every way I can."
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