King Hoel (, "Hoel the Great"; ), also known as Sir Howel, Saint Hywel and Hywel the Great, was a late 5th- and early 6th-century member of the ruling dynasty of Cornouaille. He may have ruled Cornouaille jointly after the restoration of his father, Budic II of Brittany, but he seems to have predeceased his father and left his young son, Tewdwr, as Budic's heir. Hywel appears in Welsh mythology and the Matter of Britain as a "king of Brittany". A relative of Arthur, he was one of his most loyal allies (or, sometimes, knights) and was said to have helped him conquer "Gaul" (northern France). Life The historical Hywel was the son of Budic II, king of Cornouaille in northwest Brittany. For all or most of his childhood, a usurping cousin ruled in Budic's place and the family resided in exile with Aergol Lawhir, king of Dyfed in sub-Roman Britain. He was credited with the foundation of Llanhowell (now in Llanrhian) during this time and, as "Saint Hywel", was revered by a local cult as its patron saint. The family was eventually restored to their home in Cornouaille, where Hywel may have ruled jointly with his father. He died shortly before he would have inherited the throne, however, and Budic's attempts to enlist his neighbour Macliau's support for the succession of Hywel's son Tewdwr ended badly. After Budic's death, Macliau invaded and the boy was forced into exile in Penwith. Legend While early Welsh sources say he was the son of Budic II, in later legend he evolves into the son of Emyr Llydaw and sometimes also the father of Tudwal by Saint Pompeia of Langoat. David Nash Ford was of the opinion that Emyr Llydaw was a title of Budic's—"emperor of Brittany"—eventually mistaken for a name in its own right. As a son of Budic, he was recorded as a nephew of Arthur. He was said to have visited Arthur's court during his early exile and to have returned to help Arthur against the Saxons after the family's restoration in Brittany. Landing at Southampton, his army was credited with assisting Arthur at the Battle of Dubglas, the Siege of Caer Ebrauc (i.e. York), and the Battle of Cat Celidon Coit. It was then bottled up and besieged in turn at Dumbarton Castle ("Caer-Brithon"). Hoel was also said to have been at the Battle of Badon before conquering France