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 he returned to England, leaving John in charge of Sir Walter Manny and three other knights. He accompanied his father to Calais on 9 October to assist at the liberation of King John and the ratification of the treaty. He rode with John to Boulogne, where he made his offering in the Church of the Virgin. He returned with King Edward to England at the beginning of November. On 10 October 1361 the prince, now in his 31st year, married his cousin Joan, countess of Kent, daughter of Edmund of Woodstock, Earl of Kent, younger son of Edward I, and