Princess Kate carefully designed her lace Alexander McQueen bridal gown, which has become iconic among brides, but Prince William had much less say when it came to his attire.
Prince Harry detailed the days leading up to the Prince and Princess of Wales' 2011 royal wedding in his memoir, Spare, which was released in Spain on Thursday, explaining that his elder brother actually wanted to wear something entirely different.
WATCH: Prince Harry's unexpected comments on Prince William and Princess Kate's wedding
The Duke of Sussex said that his brother hardly slept the night before he walked down the aisle, and admitted he was "gloomy" and "frustrated" that his grandmother, the late Queen Elizabeth II, had insisted he wore his bright red Irish Guards uniform as he had recently been appointed as a colonel - his most senior military position.
The red jacket featured a gold trim, and he wore it with black trousers and a blue sash – an outfit Harry described as dapper.
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Prince William didn't have a choice with his bright red Irish Guards uniform at his wedding
However, William reportedly asked to wear the cavalry uniform and frock coat of the Royal Guard, a request that was quickly dismissed by Her Majesty.
William has previously spoken about that moment to journalist, Robert Hardman, who reported his exchange with the Prince in the MailOnline. William said: "I wanted to decide what to wear for the wedding.
Prince Harry discussed his brother's wedding in his book, Spare
"I was given a categorical: 'No, you’ll wear this!' he said. "So you don't always get what you want, put it that way…But I knew perfectly well that it was for the best. That 'no' is a very good 'no'. So you just do as you’re told!"
Harry's book also made several more revelations about William and Kate's big day. According to the royal, his brother was "drunk" as they greeted members of the public on the Mall.
Harry described rolling down the car windows and offering his groom-to-be brother a mint to help mask the scent of the rum he had been drinking the previous evening.
Meanwhile, he also confessed that he was not William's best man, as it was previously assumed, and that he gave Kate a cheeky leathery ermine thong during his speech – a gift that had been sent to the royal from a member of the public on her wedding day.
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