Prince Harry chose Prince William to be his best man — here's why that breaks royal wedding protocol

• Prince Harry was Prince William's best man at his wedding.
• Technically, a royal wedding can't have a best man, only "supporters."
• Prince William broke royal protocol to make Prince Harry his best man, and now Prince Harry will do the same when he marries Meghan Markle.

British royal weddings technically don't include a best man in the proceedings. But that hasn't stopped royals from breaking protocol and giving someone the honorary title, anyway.

Marlene Koenig, a British and European royalty expert, told Town & Country that there's no such thing as a best man in royal weddings — only "supporters."

Still, Prince William broke royal protocol when he made Prince Harry his best man in his 2011 wedding to Kate Middleton.

Kensington Palace confirmed Thursday that Prince Harry has chosen Prince William to be his best man when he marries Meghan Markle. 

"The Duke of Cambridge is honoured to have been asked, and is very much looking forward to supporting his brother at St George's Chapel, Windsor on May 19th," the palace announced in a tweet.

Prince Harry and Meghan Markle will wed in spring 2018 at St. George's Chapel at Windsor Castle. It remains to be seen who else will have an official role in the ceremony.

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