1911 Encyclopædia Britannica/Alençon, Counts and Dukes of
ALENÇON, COUNTS AND DUKES OF. The first line of the counts of Alençon was founded by Yves, lord of Bellesrne, who in the middle of the 10th century possessed and fortified the town of Alençon. His successors, involved in all the wars of the kings of England in Normandy, were alternately deprived and repossessed of their domains, according to the fluctuations of fortune between the rival parties. Mabille, countess of Alençon and heiress of this family (d. 1082), married Roger of Montgomery, and from them descended a second house of Alençon which became extinct in the person of Robert IV.; the county of Alençon was then joined to the royal domain. It was successively granted as an appanage to Peter, son of St Louis (1268), and to Charles, count of Valois, brother of Philip the Fair (1293). The third house of Alençon sprang from Charles, second son of the count Valois, who was killed at the battle of Crécy in 1346. The countship of Alençon was raised to a peerage in 1367 and into a dukedom in 1414. John, 1st duke of Alençon, was killed at Agincourt on the 25th of October 1415, after having with his own hand slain the duke of York. His son, also named John, was dispossessed of his duchy by the king of England, but reconquered it in 1449. In 1524 the dukedom of Alençon reverted to the crown, in consequence of the death of the duke Charles IV. without issue of his marriage with Margaret, sister of Francis I. It was given as a jointure to Catherine de' Medici in 1559, and as an appanage to her son Francis in 1566. It was pawned by Henry IV. to the duke of Württemberg, and subsequently it passed to Gaston, duke of Orleans, duchess of Guise; to Charles, duke of Berry, grandson of Louis XIV. (1710); and to Monsieur (Louis XVIII.), brother of Louis XVI.
The title of duc d'Alençon was given to Ferdinand of Orleans, son of the duc de Nemours, and grandson of Louis-Philippe.