Edward the Black Prince the party of Montfort, and Chandos won the Battle of Auray (29 September 1364) against the French. As the leaders of the free companies which desolated France were for the most part Englishmen or Gascons, they did not ravage Aquitaine, and the prince was suspected, probably not without cause, of encouraging, or at least of taking no pains to discourage, their proceedings. Accordingly on 14 November 1364 Edward III called upon him to restrain their ravages. In 1365 the free companies, under Sir Hugh Calveley and other leaders, took service with Bertrand du Guesclin, who employed them in 1366 in
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