He had lands and castles in Normandy, which John put under sequestration, and ordered the officers commanding in them to deliver up to him.

Six of them, the commandants of the castles of Cherbourg and Evreux, amongst others, refused, believing, no doubt, that in betraying France and her king, they were remaining faithful to their own lord.
At several points in the kingdom, especially in the northernprovinces, the first fruits of the war were not favorable for the English.

King Edward, who had landed at Calais with a body of troops, made an unsuccessful campaign in Artois and Picardy, and was obliged to re-embark for England, falling back before King John, whom he had at one time offered and at another refused to meet and fight at a spot agreed upon.
But in the south-west and south of France, in 1355 and 1356, the Prince of Wales, at the head of a small picked army, and with John Chandos for comrade, victoriously overran Limousin, Perigord, Languedoc, Auvergne, Berry, and Poitou, ravaging the country and plundering the towns into which he could force an entrance, and the environs of those that defended themselves behind their walls.

He met with scarcely any resistance, and he was returning by way of Berry and Poitou back again to Bordeaux, when he heard that King John, starting from Normandy with a large army, was advancing to give him battle.

John, in fact, with easy self-complacency, and somewhat proud of his petty successes against King Edward in Picardy, had been in a hurry to move against the Prince of Wales, in hopes of forcing him also to re-embark for England.