The royal wedding of Prince Harry and Meghan Markle sparked controversy following the issue behind the infamous tiara. 

The former "Suits" star officially joined the Firm in May 2018 after she tied the knot with Prince Harry in the famous St George's Chapel at Windsor Castle in the U.K.

Shortly after, the newlyweds were proclaimed HRH Duke and Duchess of Sussex and held the title of Baron and Baroness of Kilkeel. 

Meghan Markle's Tiara Fiasco

During the wedding, then 36-year-old Markle walked down the aisle with the famed art deco Queen Mary Bandeau tiara, which her then-fiance helped her pick out.

Reports previously cited that the said accessory was given to Queen Mary in 1893 by the County of Lincoln when she married King George V. 

Unfortunately, Meghan Markle initially wanted a different tiara--the Greville Emerald Kokoshnik crown worn by Princess Eugenie on her wedding with the British wine merchant, Jack Brooksbank (precisely six months after the Sussexes wedding).

The said headpiece is the most expensive royal wedding tiara in the collection, amounting to a whopping worth $13 million (£10 million).

Moreover, rumors also sparked that this caused an alleged rift between Prince Harry and the Queen's dresser Angela Kelly after Queen Elizabeth II forbade Meghan to wear the crown. 

"Meghan cannot have whatever she wants. She gets what tiara she's given by me," the Queen allegedly told Kelly. 

Now, royal biographer and historian Robert Lacey shed light regarding the real reason why the 94-year-old monarch did not allow the former actress to walk down the aisle wearing the emerald tiara. 

The Emerald Tiara's Problematic History

In his new book "Battle of Brothers: William and Harry - The Inside Story of a Family in Tumult," Lacey delved into the insight of Her Majesty when she said no to Markle's request. 

"Unconfirmed by the palace - but not denied - we were told that the Queen felt that she had to say 'no' to Meghan's first choice, a beautiful emerald headdress that was said 'to have come from Russia," the book read, as obtained by The Mirror.

"This was code for a sensitive origin, meaning that the treasure was one of those that had found its way into Windsor hands through 'undefined' not to say dodgy channels-and for an undisclosed price-in the aftermath of the Russian Revolution."

Furthermore, the bombshell biography also revealed that the palace seldom used the tiara on public display due to the controversy attached to it. 

"There was a scandal attached. For this reason, the emerald tiara was seldom, if ever, put on public display, and it would suit neither the palace nor Meghan herself that spring if newspapers started speculating about which Tsrist princess had worn the tiara and how she had been assassinated."

The royal biographer also explained that Prince Harry was unaware of the story behind the tiara, prompting him to feel upset and angered after his fiancee was told she couldn't wear it. 

"Unfortunately, Harry's ignorance of both history and family tradition meant that he had no understanding of this subtlety," the author wrote. 

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