Dukedoms of the British Isles by reign Dukedoms of the British Isles by reign This page lists extant dukedoms in the Peerages of the British Isles, listed by the monarch who created them—see also List of dukedoms in the peerages of Britain and Ireland. King Edward III first created the title Duke of Cornwall, the first dukedom in the British Isles, for his son and heir Edward, called the Black Prince. Since 1421 the title has automatically been held by the eldest son of and heir apparent to the sovereign. Since his mother's taking the throne in 1952 the title has been held by Prince Charles, who
Edward the Black Prince differenced royal arms. His younger brother, John of Gaunt, used a similar shield on which the ostrich feathers were ermine. Edward's "shield for peace" is believed to have inspired the badge of three ostrich feathers used by later Princes of Wales. Edward married his cousin, Joan, Countess of Kent (1328–1385), on 10 October 1361. She was the daughter and heiress of Edmund, Earl of Kent, the younger son of King Edward I by his second wife Margaret of France. They had two sons, both born in Aquitaine: From his marriage to Joan, he also became stepfather to her children by