William and Kate's New Royal Titles Explained

Royally confusing!

Prince William and brand-new-wife Kate Middleton are now officially the Duke and Duchess of Cambridge! Why not just Prince and Princess of Wales? A Palace source tells Us Weekly: "It's royal protocol for grooms to receive one or two titles on the day of the wedding, and then the bride would take each title on, too."

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The new bride's official title is Her Royal Highness The Duchess of Cambridge. And her new hubby's? His Royal Highness The Duke of Cambridge. 

So is Middleton, 29, not a princess? A source says: "Kate can also technically be called Princess William of Wales, however, the title will not be officially adopted within the Palace office."

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A source tells Us that Queen Elizabeth chose the titles for her grandson, adding: "She would have had a private conversation with William to discuss the titles, and this would have taken place more than a few months ago." 

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"The Duke of Cambridge has always been a favorite choice by the Queen for William," the source adds. "She enjoys many trips to the city, including one just earlier this week."

Following royal tradition, the Queen also gave the 28-year-old prince two additional titles. William is now officially the Earl of Strathearn and Baron Carrickfergus, linking him to Scotland and Northern Ireland.

A St. James's Palace spokesman tells Us: "Both William and Catherine are honored to receive the titles."

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