House of Valois the senior descendant of Philip IV of France. Charles' character eventually alienated both the French and English monarchs, because he readily switched sides whenever it suited his interest. In 1356, Edward, the Black Prince, eldest son and heir of Edward III, led an army to a chevauchée in France. John pursued the Black Prince, who tried to avoid battling the French king's superior force. Negotiations broke down. In the Battle of Poitiers, the French suffered another humiliating defeat, and their king was captured. Edward hoped to capitalize on the victory by invading France and having himself crowned at Reims. But
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