John of Gaunt III's rule was becoming unpopular due to high taxation and his affair with Alice Perrers, political opinion closely associated the Duke of Lancaster with the failing government of the 1370s. Furthermore, while King Edward and the Prince of Wales were popular heroes due to their successes on the battlefield, John of Gaunt had not won equivalent military renown that could have bolstered his reputation. Although he fought in the Battle of Nájera (1367), for example, his later military projects proved unsuccessful. When Edward III died in 1377 and John's ten-year-old nephew succeeded as Richard II of England, John's influence strengthened.
England in the Late Middle Ages was too ill to contribute to the war or government and returned to England where he soon died: the son of a king and the father of a king, but never a king himself. Prince Edward's brother John of Gaunt, 1st Duke of Lancaster assumed leadership of the English in France. Despite further chevauchées, destroying the countryside and the productivity of the land, his efforts were strategically ineffective. The French commander, Bertrand Du Guesclin adopted Fabian tactics in avoiding major English field forces while capturing towns, including Poitiers and Bergerac. In a further strategic blow, English dominance at sea was