France
Civil War in France
The war with England by now had brought an almost intolerable strain to France. A strong king could compensate with victories or at least strong leadership, but Charles was unable to provide this because of his bouts with madness. So there developed factions within the kingdom and these factions naturally coalesced around leading families.
Louis of Orleans emerged as one leader. He was brother to Charles and so possessed both resources and prestige. Louis favored a renewal of the conflict and a vigorous prosecution of the war. After his death, leadership of this faction was taken over by the Count of Armagnac; hence the name.
Opposition to the Armagnacs was led Philip the Bold, Duke of Burgundy and the king's uncle. Both parites were therefore very close to the throne and both could reasonably hope to influence every aspect of the war.
The Burgundians were eventually persuaded to ally themselves with the English cause, in part because of the importance of Flanders to the Duke of Burgundy and in part because the English offered very generous terms.