Routiers
The Hundred Years' War, which lasted from 1337 to 1453, was the backdrop to their pillaging. The Hundred Years' War was fought between two royal families over control of the French throne: the Plantagenets from England, and the House of Valois from France. The War, which is divided into three stages - the Edwardian War (1337-1360), the Caroline War (1369-1389), and the Lancastrian War (1415-1429) - saw the development of new tactics and weaponry that revolutionised warfare during that time period.
Brittany
The Breton War of Succession, a local episode of the Hundred Years' War, saw the House of Blois, backed by the French, fighting with the House of Montfort, backed by the English. The Montforts won in 1364 and enjoyed a period of total independence until the end of the Hundred Years' War, because France was weakened and stopped sending royal envoys to the Court of Brittany. English diplomatic failures led to the Breton cavalry commanders Arthur, Comte de Richemont (later to become Arthur III, Duke of Brittany) and his nephew Peter II, Duke of Brittany playing key roles on the French side during the deciding stages of the War (the Battle of Patay, the Treaty of Arras (1435), the Battle of Formigny and the Battle of Castillon). However, Brittany lost the Mad War against France in 1488, mostly because of its internal divisions which were exacerbated by the corruption at the court of Francis II, Duke of Brittany. Indeed, some Breton lords were fighting on the French side.