Prince Phillip married Queen Elizabeth in 1947, five years before her coronation, and his dedication to the Crown has never wavered. Photo / Getty Images
The Duke of Edinburgh has always claimed to have little interest in his legacy. But as he approaches his 100th birthday, he will be aware that the peaceful privacy he has cultivated in retirement is likely to be shattered, as the spotlight falls on him once more.
Ian Lloyd, author of a new biography, The Duke: 100 Chapters In The Life Of Prince Philip, which will be published next week, believes he will ultimately want to be remembered not for his gaffes but for his service.
"I do think he bothers about it," says Lloyd. "Michael Parker, the Duke's private secretary, said his raison d'être is to support the Queen, first, second and third."
The idea of public duty superseding the quest for self-realisation is one that has fallen out of fashion. The Duke's grandson Prince Harry has, with his wife Meghan Markle, followed a very different path and Lloyd is in little doubt over how the Duke would view their choices.
"If Meghan had consulted him about the problems she had in fitting in, I have no doubt he would have told her of his own," he says. "He would have counselled her. But he would also have said 'Put your head down and get on with it'."
The Duke, Lloyd adds, prefers to channel his energies into making the best of things.
"Prince Philip always had a profound respect for the Royal family. Duty was everything. He didn't think, 'Is this appropriate for me?' He didn't over-analyse," he says. "This idea that you should also have personal fulfilment was not something he would have considered. It's a different generation."
The Duke nevertheless has always been close to Harry. "He adores him and sees a lot of himself in him. The fact that this is Harry's wife will not have helped. He will definitely see their decision to move abroad as a dereliction of duty," says Lloyd.
His book was largely accidental. Lloyd had been researching the early life of the Queen and interviewed a string of Palace insiders. But, in doing so, he realised that he had unwittingly built up a fascinating profile of the Duke.
"He comes from a completely different background to many of the people who have joined the Royal family," he says. "He's royalty himself ... but he came from this very odd childhood with a lot of adversity."
When his mother was admitted to hospital after a breakdown in 1930, the Duke's father "took the opportunity to go off to the south of France with a mistress" and, within a period of just nine months, his four elder sisters had married German aristocrats and emigrated. Philip was shunted from pillar to post in school holidays.
"From the age of 9, he became virtually an orphan with no permanent home. It must have had a tremendous effect on him," says Lloyd.
As with Meghan, the Duke's nationality affected how he was received here. "There was an element of xenophobia about some of the criticism [of Meghan]," says Lloyd. "That was the same for Philip. Even though he had served with the Royal Navy, he was very much seen as a foreigner and many did not think him an appropriate match for a British princess."
Unlike Meghan, who this week won a privacy claim in the High Court against the Mail on Sunday, the Duke has never believed in actively defending oneself in the public arena.
"Philip's attitude is very much not to pursue these things," says Lloyd.
"Rumours of alleged affairs swirled for years but when he was approached by one supposed partner, Hélène Cordet, who asked if she should have a statement put out, his attitude was very much not. He knew it would only fan the flames."
Had Harry and Meghan asked his advice on whether to pursue their claim for the publication of extracts from a private letter Meghan had sent her father, Lloyd believes the Duke would have warned against it.
"But that's the problem really, they're an independent entity now and I doubt they would have asked," he adds.
"I'm sure that with this week's ruling, he thinks, well, they might have won the battle, but have they won the war? Does it make the public more fond of them? I'm not so sure."
The Duke withstood his own early troubles upon joining "the Firm", though his case was hardly helped by aristocratic friends of King George VI and Queen Elizabeth who disliked him intensely and made "mischief in the background".
"They were bloody to him," Earl Mountbatten's son-in-law John Brabourne is quoted as saying. "They didn't like him, they didn't trust him and it showed."
Lloyd explains: "He was far poorer than them and had this awful time fitting in. They really hated him. He was seen with great suspicion, not just by the courtiers but by the King and Queen's friends who despised him."
When a valet opened the Duke's case on his first visit to Sandringham he was "mortified" by the sight of his patched-up suits and darned socks. The King had to lend him a bow tie for supper.
Weaker characters might have buckled under the strain when in 1952, five years after their marriage, the young Princess became Queen and her husband's world came crashing down.
"Prince Philip ... had to carve out his own role," Lloyd says. And that he did, writing to his charities to make clear he had no intention of being "a sitting tenant" or just a heading on the notepaper.
He asked for a desk at the office of the National Playing Fields Association and worked there every morning. He went to Butlins to accept a cheque, wined and dined Hollywood (Frank Sinatra donated the royalties from one of his records to the NPFA) and even took up an offer to swim a few lengths of a wealthy American's swimming pool in return for a $100,000 donation.
"He doesn't like the froth of royalty, the walkabouts, anything that he considers a waste of time," says Lloyd. "At one event, he found himself shaking hands with the same group of VIPs on the way out as he did on the way in and he got very cross and said: 'That's a complete waste of time. Can't you find six or seven new ones?'"
The Duke has approached retirement with a similarly pragmatic attitude, stating wryly: "I've done my bit," an epitaph Lloyd notes he would probably appreciate.
His forthcoming 100th birthday, on June 10, is likely to be low key, with a family lunch, a group photograph and perhaps a service at St George's Chapel, Windsor.
The Duke of Sussex is likely to return to the UK for the celebrations, though without his wife and son.
"Prince Philip will have been very disappointed [with the Sussexes' departure] because his focus in life is to support the monarchy," Lloyd says.
"He would have been very saddened that the younger royals don't see it that way. Harry perhaps thought, 'Well I'm never going to be King, it's just a walk-on role', yet that's exactly what Philip had. He's never been head of his own family and he's never had a starring role. I think he found it hard – but he did try to adjust."