Meghan Markle's wedding to Prince Harry was billed as a 'fairytale', but a royal row between the bride and the Princess of Wales meant the run-up was anything but.

Meghan, 44, and Prince Harry, 41, exchanged vows before 600 guests at St George's Chapel in Windsor on May 19, 2018.

However, Prince Harry's older brother Prince William was 'suspicious' of the American actress, while the Duke of Sussex was convinced his sister-in-law, Kate 'saw Meghan as a threat', according to royal author Tom Bower in his new book about the Sussexes.

While he claims the well-documented row over bridesmaids' dresses became the 'lightning rod' for the bitterness between Kate and Meghan, the 'antagonism had started once their engagement was announced.'

Among the issues, he claims, was Meghan's frustration with strict royal protocol such as curtsying.

Indeed, Meghan herself admitted that she found the formality of the Royal Family difficult.

Speaking in the Netflix documentary Meghan and Harry, she said: 'Like I was a hugger, always been a hugger. I didn't realise that that is really jarring for a lot of Brits.' 

In his bestselling book, Mr Bower revealed that simmering tensions between the pair over royal protocol and hierarchy boiled over when Catherine and Meghan clashed over the young princess's 'ill-fitting' outfit days before the wedding. 

It marked a turning point for Catherine and Meghan, who appeared to be fast friends and made regular appearances with their husbands as the Royal Family's Fab Four.

Despite projecting an image of camaraderie, Prince Harry said there were always signs of discord between his future wife and Catherine. 

In his memoir Spare, Harry detailed how Meghan asked to borrow a lip gloss from Kate ahead of their first Royal Foundation forum summit in 2018.

He claimed that Catherine was surprised, but rummaged around in her bag before offering it to Meghan.

When Meghan applied a little gloss to her finger and rubbed it across her lips, Harry's sister-in-law reportedly made a 'disgusted' face.

Mr Bower claimed that Catherine's 'glacial freeze had destroyed any suggestion of a friendship' as the lip balm incident underscored that the women belonged to two very different worlds. 

Meghan stated the Waleses' formality was in stark contrast with her own relaxed, all-American upbringing in her and Prince Harry's Netflix special when she described the first time she met William and Catherine. 

'When Will and Kate came over, and I had met her for the first time, they came over for dinner. I remember I was in ripped jeans and barefoot,' the Duchess of Sussex said. 

'Like I was a hugger, always been a hugger. I didn't realise that that is really jarring for a lot of Brits. 

'I guess I'd start to understand very quickly that the formality on the outside, carried through on the inside.

'There is a forward-facing way of being, and then you close the door, and you relax now. But that formality carries over on both sides. And that was surprising to me.' 

In the same docuseries, Meghan expressed her disbelief when she found out that Prince Harry was expected to curtsy to his grandmother, the late Queen Elizabeth. 

Meghan performed a deeply exaggerated curtsey as she recounted the 'surreal' moment she first met the Queen while an awkward-looking Harry watched in stunned silence. 

The first time Meghan met the Queen was for lunch at Royal Lodge, shortly after she and the Duke revealed they were dating.

But she said the whole occasion felt like an antiquated banquet at Medieval Times, a family dinner theatre in the US featuring staged medieval-style games, sword-fighting, and jousting.

Meghan explained that she didn't know she would be meeting Her Majesty 'until moments before' when Prince Harry asked her if she knew how to curtsy.

Recounting the 'intense' moment when she came face-to-face with the late monarch, Meghan performed a deep, mock curtsey as Harry watched on, stone-faced, before he glanced off camera, looking awkward.

'Her mocking tone begins when she shares that "I just thought it was a joke…right?" to imply royal protocol is comedy rather than part of the culture of the country,' body language expert Judi James previously told this newspaper. 

Not only was Meghan expected to bow to Her Majesty, royal protocol also dictates that Meghan must curtsy to anyone that outranks her upon entering a room. 

Catherine's husband, Prince William is currently next in line to the throne, meaning the future Queen Consort will always rank higher than her sister-in-law Meghan. 

According to Mr Bower, Meghan's 'undisguised disdain for the Palace's hierarchy' was plain to see from the beginning and had aroused Kate's distrust' ahead of her wedding to Harry. 

'For her part, Meghan was contemptuous of the [then] Cambridges' aloofness, it being a far cry from her own personal style: Kate was boring; William had cried himself to sleep at Eton. Both were so detached from her reality,' Mr Bower said. 

He added that Meghan had failed to understand how seriously the Royal Family took their roles within The Firm, adding: 'Duty, hard work, and self-sacrifice without a big pay cheque was alien to someone brought up in Hollywood.' 

So, when the pair faced off over three-year-old Charlotte's white bridesmaid dress, Catherine and Meghan, it was against the backdrop of 'conflicting, undisguised emotions', said Mr Bower. 

The incident has been revisited several times since 2018, with biographers and even Prince Harry sharing an insider's account of what happened on that fateful day. 

It was initially claimed that Meghan made Catherine weep, a suggestion that so incensed the Sussexes they went to war with their press office and demanded they put out a correction.

When officials refused, saying it would spark more questions about the incident and set a precedent for speaking about private family matters, the couple decreed that it was another example of how the palace was unwilling to stand up for them.

Indeed, it was one of the first issues to be tackled by Meghan in her Oprah interview, with Harry subsequently insisting in their Netflix docuseries that it demonstrated how the institution was willing to lie to protect his brother but not tell the truth for them.

The Duke also addressed the conflict in his controversial memoir Spare, when he insisted the fight was driven by the Princess of Wales, who appeared irritated that it had taken Meghan a day to get back to her about the problem.

He claimed the disagreement between the two was further exacerbated by Catherine's unwillingness to visit Meghan's tailor at Kensington Palace and suggestions that they hold a party for the page boys when his bride-to-be was dealing with the 'chaos' surrounding her father Thomas Markle.   

Harry wrote: 'Meg didn't reply to Kate straight away. Yes, she had endless wedding-related texts, but mostly she was dealing with the chaos surrounding her father. So the next morning she texted Kate that our tailor was standing by.'

She told her that his name was Ajay and he was ' at the palace'.

'This wasn't sufficient,' Harry goes on to write darkly.

After setting up a time to speak later that afternoon, Harry writes that Kate complained: 'Charlotte's dress is too big, too long, too baggy. She cried when she tried it at home.'

Meghan snapped back: 'Right, and I told you the tailor has been standing by since 8am. Here. At KP. Can you take Charlotte to have it altered, as the other mums are doing?'

According to Harry's version of events, Kate replied: 'No, all the dresses need to be remade.' And said she had discussed the issue with her 'own wedding designer' who agreed. 

While promoting the book in an interview with Good Morning America, Harry was asked for examples of how the palace put a negative spotlight on Meghan in order to protect other royals.

Harry told the interviewer: 'It's so petty but the bridesmaids' dresses. While I was writing the book we were on version 29 or 30, all of which involved my wife supposedly making numerous people within my family cry which simply wasn't the case.

 'For historical reference, the truth needs to be there and it needs to come from me.'

Harry and Meghan tied the knot on May 19, 2018, in a lavish royal wedding at St George's Chapel. 

The couple, who quit the royal family in 2020 and moved to Montecito, recently marked their son Prince Archie's seventh birthday, with a new photo of the Duke and his firstborn. 

The Duchess gave her Instagram followers an intimate glimpse inside her and Prince Harry's bedroom at Frogmore Cottage by sharing a rare baby photo of the young royal taken during their time living in the UK. 

Meghan's photograph showed the then-newborn sleeping peacefully on Harry's chest, as the prince gazed fondly at his son.

It comes after the Duchess joked about renewing her vows with Prince Harry in a much more informal way than their royal wedding. 

During the Sussexes' quasi-royal tour of Australia, she told YouTubers Sean Skeels and Marley Whatarau, who gifted Meghan a pair of men's swimming briefs, that's going to be for my husband'.

Thanking the internet chefs for the 'Aussie bum' budgie smugglers, Meghan continued: 'We might renew our vows with him wearing these.'