Though the future king, 42, normally goes by the Prince of Wales, Prince William and his wife, Princess Catherine, 42, are called the Duke and Duchess of Rothesay whenever they visit Scotland.
According to People, dating back to 1469, the Duke of Rothesay is a traditional royal title that is often given to the male heir to the Scottish throne and the wife of the heir becomes the Duchess of Rothesay.
In September 2022, King Charles named his oldest son as the new Duke of Rothesay as well as the new Prince of Wales in his first televised speech following the passing of his mom, Queen Elizabeth II. “Today, I am proud to create him Prince of Wales,” the newly crowned monarch said at the time. “With Catherine beside him, our new Prince and Princess of Wales will, I know, continue to inspire and lead our national conversations.”