Edward the Black Prince compelling Peter of Castile to flee from his kingdom, and in setting up his bastard brother, Henry of Trastámara, as king in his stead. Peter, who was in alliance with Edward III, sent messengers to the Black Prince asking his help, and on receiving a gracious answer at Corunna, set out at once, and arrived at Bayonne with his son and his three daughters. The prince met him at Capbreton, and rode with him to Bordeaux. Many of the prince's lords, both English and Gascon, were unwilling that he should espouse Peter's cause, but he declared that it was not
Edward the Black Prince possible that this is where the title had its origins. The French soldier Philippe de Mézières refers to Edward as the greatest of the "black boars" – those aggressors who had done so much to disrupt relations within Christendom. Other French writers made similar associations, and Peter Hoskins reports that an oral tradition of "L'Homme Noir", who had passed by with an army, survived in southern France until recent years. In Shakespeare's "Henry V", the King of France alludes to "that black name, Edward, Black Prince of Wales". John Speed reported in 1611 that the Black Prince was so named