John V, Duke of Brittany

John V the Conqueror (in Breton Yann IV, in French Jean IV) (1339 – 1 November 1399), was Duke of Brittany and Count of Montfort, from 1345 until his death. He was son of John de Montfort and Joanna of Flanders. His father claimed the title John IV, Duke of Brittany, but was largely unable to enforce his claim for more than a brief period. Because his father's claim to the title was disputed, the subject of this article has often been numbered Jo... more

John V the Conqueror (in Breton Yann IV, in French Jean IV) (1339 – 1 November 1399), was Duke of Brittany and Count of Montfort, from 1345 until his death. He was son of John de Montfort and Joanna of Flanders. His father claimed the title John IV, Duke of Brittany, but was largely unable to enforce his claim for more than a brief period. Because his father's claim to the title was disputed, the subject of this article has often been numbered John IV, while his father has been referred to as simply "John de Montfort". He is still numbered John IV by some historians and is still more commonly known by that designation (Jean IV) in France, since the French monarchy, unlike the English, never acknowledged his father's title. The first part of his rule was tainted by the Breton War of Succession, fought by his father against his cousin Joanna of Penthièvre and her husband Charles of Blois. With French military support Charles was able to control most of Brittany. After his father's death... less