Caradoc was the son of Ysenne, the beautiful niece of Arthur.  He was ignorant who his father was, till it was discovered in the following manner.  When the youth was of proper years to receive the honors of knighthood, King Arthur held a grand court for the purpose of knighting him.  On this occasion a strange knight presented himself, and challenged the knights of Arthur's court to exchange blow for blow with him.  His proposal was this,—to lay his neck on a block for any knight to strike, on condition that, if he survived the blow, the knight should submit in turn to the same experiment.  Sir Kay, who was usually ready to accept all challenges, pronounced this wholly unreasonable, and declared that he would not accept it for all the wealth in the world.  And when the knight offered his sword, with which the operation was to be performed, no person ventured to accept it, till Caradoc, growing angry at the disgrace which was thus incurred by the Round Table, threw aside his mantle and took it.  "Do you do this as one of the best knights?" said the stranger.  "No," he replied, "but as one of the most foolish."  The stranger lays his head upon the block, receives a blow which sends it rolling from his shoulders, walks after it, picks it up, replaces it with great success, and says he will return when the court shall be assembled next year, and claim his turn.  When the anniversary arrived, both parties were punctual to their engagement.  Great entreaties were used by the king and queen, and the whole court, in behalf of Caradoc, but the stranger was inflexible.  The young knight laid his head upon the block, and more than once desired him to make an end of the business, and not keep him longer in so disagreeable a state of expectation.  At last the stranger strikes him gently with the side of the sword, bids him rise, and reveals to him the fact that he is his father, the enchanter Eliaures, and that he gladly owns him for a son, having proved his courage and fidelity to his word. (The Age of Chivalry, Bulfinch, 1863)