Lancaster's chevauchée of 1346 was a series of offensives directed by Henry, Earl of Lancaster, in southwestern France during autumn 1346, as a part of the Hundred Years' War. The year had started with a "huge" French army under John, Duke of Normandy, son and heir of King Philip VI, besieging the strategically important town of Aiguillon in Gascony. Lancaster refused battle and harassed the French supply lines while preventing Aiguillon from being blockaded. After a five-month siege the French were ordered north to confront the main English army, which on 12 July had landed in Normandy under Edward III of England and commenced the Crécy campaign.