Prince William and Kate Middleton's New Royal Titles Are Finally Official

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Swiftly following the death of Queen Elizabeth II, Prince William and Kate Middleton were appointed the Prince and Princess of Wales. Despite their title changes, which were bestowed upon them by King Charles III, the royal couple have not officially been recognized as the Prince and Princess of Wales—until now.

The royal titles became official on Friday when the Letters patent passed the Great Seal of the Realm on Feb. 13. According to the Royal Collection Trust, Letters patent are an open document from the sovereign, which can be used to express the Sovereign's will, such as to confer an office or create a new peerage. The notice from the Crown Office was printed in The Gazette and solidified Prince William and Kate as the Prince and Princess of Wales.

"In accordance with the direction of HIS MAJESTY THE KING Letters Patent have passed the Great Seal of the Realm, dated the 13th February 2023 for creating His Royal Highness Prince William Arthur Philip Louis, Duke of Cornwall Rothesay and Cambridge, Earl of Carrick and Strathearn, Baron of Renfrew, Baron Carrickfergus, K.G., K.T., Lord of the Isles and Prince and Great Steward of Scotland, PRINCE OF WALES and EARL OF CHESTER," the notice said.

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Prior to being named the Prince and Princess of Wales, Prince William and Princess Catherine held the titles of Duke and Duchess of Cambridge—positions given to them by Queen Elizabeth on their wedding day in 2011. In addition to being named Duke and Duchess of Cambridge, the royals also became the Earl and Countess of Strathearn as well as Baron and Baroness of Carrickfergu.

After the queen's Sept. 8, 2022 death, Prince William and Princess Catherine were elevated to the Duke and Duchess of Cambridge and Cornwall. Then one day later, following King Charles III's first speech as sovereign, he named the couple the Prince and Princess of Wales.

"Today, I am proud to create him Prince of Wales, the country whose title I have been so greatly privileged to bear, during so much of my life," the King said about Prince William. "With Catherine beside him, our new Prince and Princess of Wales will, I know, continue to inspire and lead our national conservations, helping to bring the marginal to the center ground, where vital help can be given," the King said.