Duke of Aquitaine House of Valois claimed supremacy over Aquitaine. In 1360, both sides signed the Treaty of Bretigny, in which Edward renounced the French crown but remained sovereign Lord of Aquitaine (rather than merely duke). However, when the treaty was broken in 1369, both these English claims and the war resumed. In 1362, King Edward III, as Lord of Aquitaine, made his eldest son Edward, Prince of Wales, Prince of Aquitaine. In 1390, King Richard II, son of Edward the Black Prince appointed his uncle John of Gaunt Duke of Aquitaine. This grant expired upon the Duke's death, and the dukedom reverted
Edward the Black Prince already warned his father of the intentions of the French king, but there was evidently a party at Edward's court that was jealous of his power, and his warnings were slighted. In April 1369, however, war was declared. Edward sent the Earls of Cambridge and Pembroke to his assistance, and Sir Robert Knolles, who now again took service with, him, added much to his strength. The war in Aquitaine was desultory, and, though the English maintained their ground fairly in the field, every day that it was prolonged weakened their hold on the country. On 1 January 1370 the Black