Jean III of Brittany was a nobleman who ruled as the Duke of Brittany from 1341 until his death in 1364. He was born in 1286 and was the son of Jean II of Brittany. His reign was marked by conflicts over the succession of the duchy, leading to the War of the Breton Succession, which involved various factions and external powers, including England and France. During his rule, Jean III sought to strengthen the duchy's independence and maintain its unique identity. He was known for his efforts to secure alliances and manage the political landscape of medieval France. His legacy includes the continued struggle for Breton autonomy and the eventual unification of Brittany with France.