The House of Brittany was a noble family that ruled the region of Brittany in northwestern France. It emerged in the 9th century and played a significant role in the political landscape of medieval France. The house produced several notable dukes, including Duke John IV, who was instrumental in asserting Brittany's independence. Throughout its history, the House of Brittany was involved in various conflicts, including the Hundred Years' War. In 1532, Brittany was officially united with France, marking the decline of the house's power. Despite this, the legacy of the House of Brittany remains significant in the history of the region.