FitzClarence

Fitzclarence or FitzClarence is a pseudo-Anglo-Norman name meaning "son of Clarence"—it usually refers to a bastard son of a Duke of Clarence, or a descendant thereof, and was used by them as a surname.

The FitzClarence family was an illegitimate branch of the House of Hanover. Prince William, Duke of Clarence, and future king William IV of the United Kingdom, had at least ten children with his mistress Dorothea Jordan, all of whom took the surname FitzClarence. All of them were also granted by their father the rank of a marquess' younger sons or daughters.

The Duke of Clarence's eldest surviving illegitimate child, George FitzClarence (1794–1842), was created Earl of Munster in 1831 and his male-line was continued until the death of Anthony FitzClarence, 7th Earl of Munster in 2000. Two of Lord Munster's brothers, Frederick and Augustus (a priest), had issue that were also part of the family. Five daughters of William IV and Dorothy Jordan were married to nobles or prominent military figures, including William Hay, 18th Earl of Erroll, Lucius Cary, 10th Viscount Falkland, and Admiral Lord John Hallyburton. Only one, Mary, had no children.

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