In contrasts, French armies depended heavily upon the military obligations of the chivalrous classes, providing men-at-arms, and a levied infantry or town militias, often of poor quality.  Missile-men were commonly Genoese mercenary crossbowmen, drawn from the royal fleets.  Such forces proved difficult to muster, being tied down in garrison duty, and being tactically inflexible in the face of the English ‘system’.

Certainly English tactics were crucial in providing victories, often against the odds, but this does not mean that the English strategy of chevaucje was a battle-seeking one.  The chevauchies resulting in the battles of Crecy (1346) and Poitiers (1356) were untypical, although both gave Edward important political advantages.  The chevauchies of the 1370’s and 1380’s were less successful.  The French had learnt not to offer battle, and the English gained no fortifications.

1340 saw the first real conflict between France and England with the Battle of Sluys.  The outcome of this was a decisive English naval victory, but the following land campaign achieved no more than an unsuccessful siege of Tournai.  These costly expeditions bankrupted the English government and forced them to change strategy.  England adopted, for the next two decades, a style of guerrilla warfare. The English established oppressive ransom districts to support their garrisons in Brittany, whose captains made fortunes.

In April 1356, John II (king of France since 1350) arrested Charles, king of Navarre, for treachery.  This brought Philip of Navarre, Charles’ brother, into Edward’s camp, this was a useful ally as the brothers’ estate included parts of Normandy.  Edward seizing his chance redirected his troops, under Henry of Lancasters command, intended for Brittany to Normandy, were they joined forces with other ally units and lifted the siege of Pont Audemer, from there they swept south via Breteuil, Conches and Verneuil were King John mustered troops to slowly to oppose them.  They continued to march south via Argentian then Torigny. Lancaster then launched another chevauchee out of Brittany to join up with prince Edward, who was advancing north from Bergerac.  Edward spent 7-11 August at Tours, probably waiting for Lancaster, whose advance was barred by the swollen Loire River.  Unaware of this Edward got trapped just south of Poitiers by King John, who had learnt of Edwards’s positions by prisoners he had captured.  Edward took up a strong position and was able to nullify John’s numerical superiority and then managed to capture the French King (19 September 1356) and hold him for ransom.

Edward was provoked in 1359 to invade North France again, over royal ransom wrangling. He intended to take Reims and be crowned king there.  When the city defied siege, Edward, ever the opportunist, gave up his claim to the French throne in return for confirmation of the widest extent of lands held by the English crown for 200 years (Treaty of Bretigny, 1360)  His original aim of securing Gascony had been greatly exceeded as the campaigns of the 1340’s created their own momentum of plunder and glory, and the windfall of King John’s capture gave him a trump card in negotiations.  His strategy had won huge gains, but it was not to prove fallible.