They say that good things come to those who wait, and that certainly seems to have been the case for King Charles and Queen Camilla, who celebrate their 20th wedding anniversary on 9 April. For a couple that many believed would never be able to marry, let alone mark such a significant milestone, it is little short of an astonishing achievement.

“For a long time, people like me would have told you there was absolutely no way Charles could marry Camilla, that it was absolutely out of the question and wasn’t going to happen,” royal historian Hugo Vickers tells OK! “But it did happen – and it worked.”

Charles and CamillaCharles and Camilla

Charles and Camilla announced their engagement on Feb 10, 2005 -Credit:Getty

In fact, few love stories have endured quite like that of our King and Queen – and few have been beset by so many obstacles. There was an “immediate attraction” when Prince Charles and Camilla Rosemary Shand first crossed paths at a polo match in Windsor Great Park in 1970.

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“From the moment he met her, he seemed struck by her,” says Hugo. “Obviously, they just clicked and it’s clear that something about her appealed to him very early on.”

Despite such early promise, Charles’s burgeoning naval career cut short any prospect of long-term romance and Camilla soon fell into the arms of dashing British Army officer, Andrew Parker Bowles. The couple married in 1973 and had two children, Tom and Laura, while Charles went on to marry Lady Diana Spencer in 1981. But Camilla was never far from his thoughts and, five years later, he and Mrs Parker Bowles reportedly rekindled their affair.

Aware of her husband’s adultery, an increasingly unhappy Princess Diana ignited a royal scandal when she exposed his and Camilla’s clandestine relationship in Andrew Morton’s 1992 book, Diana: Her True Story. This lead to their separation and eventual divorce four years later. But for Charles, now 76, and Camilla, 77, worse was to come.

In 1995, Diana’s explosive BBC Panorama interview – in which she memorably revealed “there were three of us in this marriage” – sent their reputations into freefall. Camilla, still smarting from the public humiliation of the “Camillagate” tapes scandal in 1993, became one of the most vilified figures in Britain.

Two years later, when Diana was killed in a Paris car crash, it seemed there would be no way back for her, with even the late Queen Elizabeth said to have branded her “that wicked woman”. But Camilla wasn’t one to be cowed and with grit, patience and a surprising amount of good humour – she managed to turn things around.

“Camilla Parker Bowles was actually quite extraordinary from the outset,” says royal author Katie Nicholl. “When you consider the public hatred she had to deal with, the intense media attention and scrutiny, being the most reviled woman in Britain
 obviously it wasn’t easy. And yet she went about her life, she looked after her children and she got through it. I think that gives you an indication as to the mettle of this woman.”

Charles and CamillaCharles and Camilla

Charles and Camilla tied the knot in April, 2005 -Credit:Clarence House

In 1998, a nervous Camilla met Princes William and Harry for the first time, but the Queen was yet to be convinced by her and Charles’s relationship and didn’t attend her son’s 50th birthday celebrations, knowing Camilla would be there.

It was another two years before Camilla was formally introduced to her future mother-in-law, at a birthday luncheon for King Constantine of Greece at Highgrove. Slowly but surely, the Queen’s attitude was thawing and, by the time Charles and Camilla announced their engagement in 2005, the couple finally had her blessing.

Although she didn’t attend the civil ceremony at Windsor Guildhall, the monarch was present at the service of prayer at St George’s Chapel and later gave a warm-hearted and, according to Katie, “unusually sentimental speech” in which she declared she was “very proud” of her son and his new bride.

Camilla had finally gained acceptance, but despite her famously British ‘stiff upper lip’, she has admitted she found the earlier backlash “deeply unpleasant”. It was only the unwavering support of her loved ones – especially King Charles – that helped her weather the storm.

“It was incredibly difficult for her,” says Katie. “But she had a very loyal network of close family and friends who were there to pick her up and support her during the hard times. I think she would probably say she wouldn’t have got through it without them. I also think that the love she has for Charles – and has always had for him – got her through. When you love someone that deeply, that acts as a great support and brings resilience.”

Prince Charles, Prince of Wales looks on as Camilla, Duchess of CornwallPrince Charles, Prince of Wales looks on as Camilla, Duchess of Cornwall

Charles praised Camilla for her unwavering support -Credit:Getty

In 2015, Charles himself poured praise on the way Camilla dealt with what he described as a “real, real challenge”, telling CNN, “She’s been brilliant in the way she’s tackled these things.” Hugo sees their forthcoming anniversary, which comes just over 12 months after the couple were rocked by King Charles’s cancer diagnosis, as clear evidence that they have “proved the cynics wrong”. He says, “They’re very, very devoted to each other and there’s no question that Charles is a much happier, more relaxed man than he used to be.”

His improved state of mind is no doubt linked to his mother’s historic gesture, on the eve of her Platinum Jubilee in 2022, expressing her wish for Camilla to be known as Queen Consort upon Charles’s accession. In doing so, she not only signalled to the public that Camilla had her full acceptance, but also conveyed a deep respect for the couple’s enduring marriage.

“Camilla’s rehabilitation has been extraordinary and I think the late Queen played a major role in that,” says Katie. “And, of course, that word ‘consort’ has been dropped since the Coronation. She is Queen Camilla and that was always how Charles wanted it. Today, there is no doubt that our King and his “darling wife”, as he regularly refers to her, are as in love as ever.

“I think in many ways theirs is the ultimate love story,” says Katie. “It started as a dalliance at the polo. That was where the flame of romance was lit and it’s a flame that never really went out. It’s had many challenges on the way, many obstacles, and has not only survived, but has become stronger and more vibrant with the years.”

This journey from scandal to stability is all the more remarkable given that their relationship was once condemned not only by the most senior members of the royal family, but by millions around the world.

“When you look at them as a couple, you just see two people who are in complete partnership with each other – a hand in glove,” adds Katie. “They are a pair, they work together, and what was initially perceived as an adulterous affair that threatened to unhinge and unravel the monarchy has become, ironically, one of the greatest of all royal love stories.”