Prince Harry was given the title Duke of Sussex by his grandmother Queen Elizabeth on Saturday, Buckingham Palace said, meaning his American fiancee Meghan Markle will become a duchess after the couple wed later.
Traditionally the monarch bestows titles on princes and their spouses in the day of their wedding.
Harry was also named Earl of Dumbarton and Baron Kilkeel, in keeping with the tradition of awarding titles from different constituent parts of the United Kingdom.
The royal duchy of Sussex was created by George III for his fifth son Augustus Frederick in 1801. Augustus died without having any children in 1843 when the dukedom became extinct.