John V of Armagnac (Fr.: Jean V, comte d'Armagnac) (1420 – 6 March 1473), the penultimate Count of Armagnac of the older branch. He was the son of John IV of Armagnac and Isabella of Navarre. Life Styled Viscount de Lomagne while his father lived, John succeeded him as Count of Armagnac when he died (5 November 1450); soon after, he started a relationship with his sister Isabelle, Lady of the Four-Valleys (Dame des Quatre-Vallées), ten years his junior, whom the chronicler Mathieu d'Escouchy accounted one of the great beauties of France and whose betrothal to Henry VI of England had been under consideration. When word got out that two boys (John and Anthony) had been born in the castle of Lectoure, the couple promised to reform their incestuous behavior. But within a few months, John solemnized the union between the two by claiming to have obtained a papal dispensation from Pope Callixtus III, shortly after their third child, a daughter called Rose (or Mascarose) was born. Other serious breaches ensued: John refused to seat a bishop of Auch selected by the King and assented to by the Pope, installing an illegitimate half-brother of his in the seat. Events came to a head in May 1455. Authorities were alerted, and a brief was issued for John's arrest, when an investigation revealed that he had forced a forged dispensation out of Antoine d'Alet, Bishop of Cambrai, a magistrate in the court of Rome. Tried in absentia in 1460 before a parlement of Charles VII, he was convicted of lese-majeste, rebellion and incest. Forces were sent to capture him but he escaped punishment by fleeing to his cousins in Aragon. Though he pleaded his case in Rome, the couple were separated and the sons declared bastards and barred from inheritance. Within a few years a new King of France, Louis XI, reinstated John in his domains, where John rashly undid his father's acts and broke faith with his promises. Betraying Louis, Armagnac was part of the league that called themselves Bien public and threatened Paris at the head of 6,000 mounted men. In 1469, Louis responded, under the pretense that John was treating with ambassadors from England, and sent an army under Antoine de Chabannes to rout him. John fled to Spain, only to reappear in 1471 in the train of the king's rebellious brother, the duc de Guyenne. Louis had John