The Queen's death has prompted an unprecedented outpouring of grief from around the world. In light of the sad news of her passing, we're taking a look back to the very beginning of her landmark 70-year reign - the moment Princess Elizabeth became Queen Elizabeth II.
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The late monarch's history was being featured in Channel 4 documentary, The Queen's Lost Family, where personal photos, letters and diaries from the royal family between 1920 and the end of World War Two were revealed. And in episode three, the programme focused on the monarch's father George VI, and his reign following brother Edward VIII's abdication. George – known as Bertie to his close friends – became King while Britain was facing many problems, and throughout his reign, he became known as the symbol of Britain's determination to win the Second World War against Germany. Following his death in February 1952, his oldest daughter Princess Elizabeth became Queen.
King George VI arrives at London Airport to say goodbye to Princess Elizabeth
At the time, Elizabeth was in Kenya with her husband Prince Philip. The couple, who had been married for five years, were making the most of a break in royal duties at a game-viewing lodge, the Treetops Hotel. They were at the start of the first lap of their Commonwealth tour, which was to also include visits to Australia and New Zealand, representing her father who was too ill to travel.
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The King, now thousands of miles away at Sandringham, had been battling cancer and his health was declining. He had waved Elizabeth and her husband off at London Airport on 31 January – it would be the very last time father and daughter saw each other.
The couple spent the day of 5 February taking personal cine footage of elephants at a nearby watering hole, before retiring to their room high up in the trees. And it was here, in the early hours of 6 February, that Elizabeth became Queen.
For the first time in the history of the world, a young girl climbed into a tree one day a Princess and after having what she described as her most thrilling experience she climbed down from the tree next day a Queen," British hunter Jim Corbett, who was also staying at Treetops at the time, wrote in the visitors' log book.
Princess Elizabeth and Prince Philip pictured in the grounds of Sagana Lodge
The King had died peacefully in his sleep at the age of 56 – but Elizabeth's remote location meant it was some time before the news reached her. It was first relayed to a senior courtier, who passed it on to the princess' private secretary, Martin Charteris, who then telephoned Prince Philip's aide, Commander Michael Parker.
By then, the royal couple had returned to Sagana Lodge, a farm some 20 miles away from Treetops which had been gifted to her as a wedding present by the Kenyan government. Commander Parker personally alerted Philip to the King's death, and it was he who broke the news to his wife. "He looked as if you'd dropped half the world on him," Commander Parker later recalled.
"He took [The Queen] up to the garden and they walked up and down the lawn while he talked and talked and talked to her." Martin Charteris arrived shortly afterwards. "She was sitting erect, fully accepting her destiny," he said of the new queen. "I asked her what name she would take. 'My own, of course.'"
John Jochimson was one of the 32 journalists following the royal couple at the time. "Myself and two other photographers drive to Sagana Lodge, hoping to take a photograph of the princess, now Queen Elizabeth, leaving for London," he said. "An official told us Her Majesty requested no pictures be taken.
"We stood silently outside the lodge as the cars drive away in a cloud of dust, not one of us taking a shot at that historic moment. Seeing the young girl as Queen of Great Britain as she drive away, I felt her sadness, as she just raised her hand to us as we stood there silent, our cameras on the ground."
Elizabeth arrived back in London to find a nation in mourning
Elizabeth arrived back in London on 7 February to find a nation in mourning, with flags flying at half-mast, theatres closed and sports events cancelled. The following day, the 25-year-old queen addressed privy councillors and representatives from the City of London and the Commonwealth at an Accession council in St James's Palace.
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"By the sudden death of my dear father I am called to assume the duties and responsibilities of sovereignty," she said. "My heart is too full for me to say more to you today than I shall always work as my father did throughout his reign, to advance the happiness and prosperity of my peoples, spread as they are all the world over."
George VI's body lay in state for three days in Westminster Hall. Some 300,000 people filed by to pay their respects, and he was buried in St George's Chapel, Windsor, on 15 February. The Queen's coronation took place on 2 June 1953.
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