The Armagnac party was prominant in French politics and warfare during the Hundred Years' War. They were allied with the supporters of Charles, Duke of Orléans against John of Burgundy after Charles' father Louis, Duke of Orléans was killed at the orders of the Duke of Burgundy in 1407. The party took its name from Charles' father-in-law, Bernard VII, Count of Armagnac, who provided much of the financing and some of the seasoned Gascon troops that beseiged Paris before their defeat at St. Cloud. Later, John of Burgundy was sent back to his lands, and Bernard of Armagnac remained in Paris and, some say, in the Queen's bed.

Charles married Bonne of Armagnac, who was only 11 at the time, partly for her dowry and the support of her father. The whole enterprise was shaky, and the term Armagnac became a derogatory term meaning rowdy or ruffian because the Gascon soldiers could only be maintained by allowing them to forage and pillage wherever they went.

• For the article on the region of France, see Armagnac (region).
• For the article on the brandy, see Armagnac (drink).