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 Armagnac, did not forget the offence, and Froissart speaks of it as the "first cause of hatred between him and the prince". A more powerful cause of this lord's discontent was the non-payment of an annual pension which had been granted him by Edward. About this time he agreed to marry Margaret of Bourbon, sister of the queen of France. The Black Prince was annoyed at this betrothal, and, his temper probably being soured by sickness and disappointment, behaved with rudeness to both D'Albret and his intended bride. On the other hand, Charles offered the lord the pension which he