It was announced on Friday 9 April 2021 that the Duke of Edinburgh sadly passed away aged 99.
A statement from Buckingham Palace read: "It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh.
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"His Royal Highness passed away peacefully this morning at Windsor Castle. The Royal Family join with people around the world in mourning his loss. Further announcements will be made in due course."
Philip had been devoted to his wife and ever since their 1947 wedding, he had stayed in the background, a steadfast support as Her Majesty carried out her vital role for the nation.
On their golden wedding anniversary in 1997, the Queen praised his devotion, saying: "He has, quite simply, been my strength and stay all these years."
Philip was the longest-serving consort of a monarch, and before he retired from royal public duties in August 2017, he carried out 250 engagements a year.
On the 70th anniversary of the D-Day landings in 2014, he accompanied the sovereign to the commemorations in France. Then in 2015, there was a state visit to Germany and a trip to Malta for the Commonwealth Heads of Government meeting.
READ: Prince Philip's sweetest family pictures with his children and grandchildren
Prince Philip and the Queen pictured by Annie Leibovitz for Vanity Fair
On the few important occasions when he was not on hand – such as when a bout of ill-health forced him to miss the service of thanksgiving for the Queen's Diamond Jubilee in 2012 – his absence was as keenly felt as if a crown had gone missing from the Tower of London
However, in the early days of their courtship, no one could have predicted that the marriage would have gone on to be such an unqualified success. Philip was a Prince without a kingdom to call his own, having entered the world as Prince Philip of Greece in 1921 on the island of Corfu.
His father was Prince Andrew of Greece, the seventh child of the country's King George I, while his mother Princess Alice of Battenberg was a great-granddaughter of Queen Victoria.
The royals at Trooping the Colour ceremony
Philip and his four older sisters endured a tumultuous childhood beset with trauma and dramas stemming from their family's exile from Greece in 1922. Princess Alice had been born deaf and suffered poor mental health. She was committed to a psychiatric clinic where she stayed for two years when Philip was eight.
This, coupled with an unreliable father who was often absent in the south of France, meant that the young royal was virtually orphaned. In 1937, the family suffered another blow when his sister Cecile, her husband and two of her sons were killed in an air crash.
Despite his difficult start, Philip emerged a strong, ambitious and formidable character. His good looks, combined with his status as a dashing young naval officer, set many ladies' hearts aflutter. But it was Britain’s young Princess Elizabeth who gave him the love and happy family atmosphere he sorely needed.
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A young Philip pictured in 1947
In 1939, when George VI visited Dartmouth Naval College with his family the Greek royal was asked to show 13-year-old Elizabeth around.
They kept in touch after the meeting, exchanging a series of heartfelt and romantic letters during World War II as Philip served with the British navy in the Indian Ocean and the Mediterranean.
He was mentioned in dispatches and became at 21 one of the youngest first lieutenants in the Royal Navy. In this capacity, he was second in command of the destroyer HMS Wallace.
During his leave, he would make frequent trips to London to visit Elizabeth and the Princess's governess, Marion Crawford, recalled how he would roar through the forecourt of Buckingham Palace in an MG sports car, "always in a hurry to see Lilibet", as her family called her.
The royal couple became engaged in April 1947
On his return from battle when Elizabeth was 19, they officially started courting. Although he'd proved his worth during the conflict, the war hero with no home or fortune was an unlikely choice of regal companion.
Nevertheless, in April 1947, the King gave his blessing for a royal wedding. The groom wrote to his beloved's mother, Queen Elizabeth, of his good fortune. "I am sure that I do not deserve all the good things that have happened to me…. to have been spared in the war and seen victory. To have fallen in love completely and unreservedly."
In another letter to the Queen Mother, he wrote: "Cherish Lilibet? I wonder if that word is enough to express what is in me."
After the nuptials, Philip became His Royal Highness The Duke of Edinburgh. He had already renounced his Greek citizenship and adopted the name Mountbatten. This was taken from his maternal grandparents, who although members of the German royal family, had adopted British nationality and translated their surname Battenberg literally into English.
Besides his family, the Duke's passions drew him in three main directions – the environment, equestrian pursuits and the welfare of young people.
In November 1947 they married at Westminster Abbey
Perhaps his greatest contribution was the Duke of Edinburgh Award Scheme, which he launched in 1956 to provide youngsters with an opportunity for personal and professional discovery.
The scheme has gone on to become one of the most successful youth programmes in the world, with more than six million young men and women gaining the award. He also lent his support to the World Wildlife Fund for Nature, and in his role as president from 1961 to 1982 toured the world to promote its cause.
During over 60 years in the spotlight, the Prince had become known for using quips to break up the routine of public engagements. He himself recognised that his jokes could be risky, concluding a tour of Australia and New Zealand in 1968 by saying: "As so often happens, I discover that it would have been better to keep my mouth shut."
Elizabeth and Philip went on to have four children; Prince Charles, born in 1948, followed by Princess Anne in 1950, and then, after a gap of ten years, Prince Andrew and finally Prince Edward.
Though his remarks could be controversial, the Queen appreciated his sense of humour.
The Queen and Prince Philip were married for almost 74 years
Prince Philip excelled in his official role as Her Majesty's consort precisely because he knew that behind closed doors, he had the traditional role of head of their family. And one of the reasons their love stood the test of time was their ability to laugh together – her husband could tease out genuine, unabashed mirth from the monarch.
He was the rock of his family. Princes William and Harry particularly valued his advice and support. When William voiced doubts about walking behind his mother Princess Diana's coffin in 1997, it was his grandfather who helped reassure him.
Philip, who was intimately acquainted with loss, offered to accompany the bereaved youngster in the most difficult journey he would ever have to take. "If I walk, will you walk with me?" he asked.
During a documentary about the Queen's life, Prince William spoke about his grandparents' bond while watching footage of the two of them smiling at one another during a photoshoot.
"I'd love to know their secret," he said. "I think it’s fantastic and I've regularly asked them both how they've managed it, because they are the most lovely couple. I hope Catherine and I have the same sort of future ahead of us, where we can be as happily married as they are after 68 years."
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