Somewhat obscure within The Arthurian Legend Cycle, ''Duke Cador'' of Cornwall. Said to be a Relative to King Arthur, this is obviously difficult to establish. Cornish Dukes and Earls for Centuries had tried to used this Myth to establish Their ''Right'' to The English Crown. As per Legend, only a ''true King'' can assume The Role (and of course, retrieve The Sword ''Excalibur''. Some ''sketchy'' historical evidence does find a Duke Cador in the 10th Century AD as a ''Warlord'', but even in this – much is put off to Literature (Fiction).