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 (in the Pyrenees) to Pamplona (the capital of Kingdom of Navarre). When Calveley and other English and Gascon leaders of free companies found that the Black Prince was about to fight for Peter, they withdrew from the service of Henry of Trastámara, and joined the Black Prince "because he was their natural lord". While the prince was at Pamplona he received a letter of defiance from Henry. From Pamplona the prince marched by Arruiz to Salvatierra, which opened its gates to his army, and thence advanced to Vitoria, intending to march on Burgos by this direct route. A body of