Charles of Blois (1319–1364)

Duke of Brittany (also known as Charles of Chatillon). His dukedom was disputed by John, Count of Montford-l'Amaury, with the support of Edward III of England, and later by the count's son. Charles was killed at the Battle of Auray.

A nephew of Philippe VI of France, he married the daughter of Guy of Brittany. On the death of his wife's uncle, John III, Duke of Brittany in 1341, his claim to the title matured but was disputed. Charles, aided by his uncle, took prisoner his rival, John, Count of Montford-l'Amaury, but was himself taken prisoner in 1347. He was released in 1356 and continued the war against his old rival's son, also called John.