As the Duke of Edinburgh, he was the longest serving royal consort in history, and our normally stoic sovereign publicly declared him as her "strength and stay".
With no guidebook to follow, Prince Philip carved out his role "by trial and error" – and most importantly – on his own terms. His acerbic and straight-talking style was the stuff of legend; it was softened by a mischievous naval gentleman's wit, steadfast sense of duty and genuine devotion to the wife he married in 1947.
WATCH: The Queen and Prince Philip's enduring love story
A case in point was his coining of the word 'Dontopedalogy'. "It's the science of opening your mouth and putting your foot in it, a science which I have practised for a good many years,'' he quipped to a group of dentists in the sixties.
The man who was part of Britain's national landscape for decades entered the world as Prince Philip of Greece.
He was born on the island of Corfu, on 10 June 1921, the youngest child and only son of Prince Andrew of Greece, who was the seventh child of the country's King George I. His mother was Princess Alice of Battenberg.
Philip was a Prince without a kingdom to call his own, and he and his four sisters endured a tumultuous childhood beset with trauma and dramas stemming from their family's exile from Greece in 1922.
Alice was born deaf and suffered poor mental health. She was committed to a psychiatric clinic when Philip was just eight.
This, coupled with an unreliable father who was often absent in the south of France, meant that the young royal was virtually orphaned.
Philip attended Gordonstoun School in Scotland
Despite this uncertain start, Philip emerged from his upbringing as a strong, ambitious and formidable character.
His good looks combined with his status as a dashing young naval officer, had the ladies' hearts aflutter. It was Britain's young Princess Elizabeth, who gave him the love and happy family atmosphere he sorely needed.
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 despatches, the equivalent of an honourable mention from his superior officer, 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.
Philip working at his desk while serving in the Royal Navy
During his leave, he would make frequent trips to London to visit her and the Princess' 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" – her family's pet name for her.
On his return 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 George VI gave his blessing for a royal wedding. 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.
Elizabeth and Philip on their wedding day in 1947
Prince Philip excelled in his official role as consort precisely because he knew that behind closed doors, he was the Queen's equal.
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.
Their grandson, Prince William, shed some light on exactly how the Queen felt about the husband's manner.
''My grandfather makes my grandmother laugh because some of the things he says and does and the way he looks at life is obviously slightly different than her so together they make a great couple."
Relationship with children and grandchildren
Although the royal patriarch's relationship with his own children – Charles in particular – was sometimes strained, he was the rock of his family. William and Harry particularly valued his advice and support.
Philip shared a close bond with grandsons William and Harry
When William voiced doubts about walking behind his Princess Diana's coffin in 1997, it was his grandfather who helped reassure him, and 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.
Besides his family, the Duke's passions drew him in three main directions – the environment, equestrian pursuits and the welfare of young people.
Perhaps his most greatest legacy is the Duke of Edinburgh Award Scheme which he launched in 1956 to provide a youngsters with an opportunity for personal and professional discovery.
The Duke carrying out his final public engagement before retiring in 2017
The scheme went 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 promoting its cause.
During more than 60 years in the spotlight, the Prince employed quips to break up the routine of public engagements.
He himself recognised that his jokes didn't always find favour, 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."
The Duke often didn't, of course. If he was the product of a less politically correct time, he also had very many old school virtues, being doughty, stouthearted and a trooper to the end. His family and many across the country and beyond will miss the power behind the throne.
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