'Mistake' the Queen made in Meghan's early days in the monarchy

When Queen Elizabeth invited Meghan Markle to join her for an official engagement to Chester in 2018, it was seen as a significant welcoming gesture.

It was a few weeks after the royal wedding and the Duchess of Sussex was front and centre, seated next to the reigning British monarch with the eyes of the world on her.

Nobody could have predicted that just two years later, there would be a divide in the monarchy so deep it would lead to the resignation of Meghan and Prince Harry.

Now, royal author Robert Lacey suggests Her Majesty made a "mistake" by inviting the newly-minted duchess on the tour.

Lacey, whose new book Battle of the Brothers is out on October 20, says the invitation was a serious error of judgement because it showed the Queen considered Meghan to be "just a routine royal".

"There is only one self-made millionaire in the Royal Family and that is Meghan Markle," he told the Daily Mail ahead of the biography's release.

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"If they had sat down with her at the start and said, "Let's talk about the things you are interested in", things might have been different.

"[But] they just sent her off to watch the Queen opening the Mersey Bridge. There is nothing wrong with that, but they made the mistake of dealing with the spare's wife thinking she was just a routine royal. She was never going to be a routine royal."

Lacey claims cracks in the relationship between William and Harry appeared much earlier than most people believe, even before Meghan arrived on the scene.

He discusses this in detail in the book, having spent months talking to royal insiders, and says the timeline matters — particularly as the future of the monarchy rests on the brothers.

"It matters," he tells the Daily Mail. "It's a question of values, even about the national morale. The idea of our modern royalty was built on the idea of these two brothers.

"What you've got to realise is that the whole strategy of the monarchy was based on them sticking together. Meghan changed all that. She is difficult. She has an incredible and dangerous level of self-belief."

While the Harry and Meghan biography Finding Freedom, written by 'friendly' journalists Omid Scobie and Carolyn Durand, painted a flattering picture of the Sussexes and their royal fall out, Lacey says he's attempted to give a more balanced version of events in Battle of the Brothers.

The author wants the book to serve as a historical document of events, which points to Prince Harry's dissatisfaction with royal life as the cause of the split.

"He finds new destiny,' Lacey says. "He realised there was something rotten at the heart of royalness that is not for him."