The Dukes of Bretagne were the rulers of the historical region of Brittany in northwestern France. This title emerged in the 9th century and continued until the late 16th century. The dukes played a significant role in the region's politics, culture, and economy, often asserting their independence from the French crown. The most notable duke was Francis II, who ruled in the late 15th century and was the last independent duke before Brittany was united with France. The Duchy of Brittany was officially annexed to France in 1532, marking the end of the dukes' sovereignty.