The Duke of Cleves was a noble title in the region of Cleves, located in present-day Germany. The title became prominent in the 14th century and was held by various rulers who played significant roles in the politics of the Holy Roman Empire. The most notable Duke was John III of Cleves, who was known for his alliances through marriage, including his connection to Anne of Cleves, the fourth wife of King Henry VIII of England. The Duchy of Cleves was part of a larger political landscape that included various principalities and territories. It was strategically important due to its location near the borders of France and the Netherlands. The region experienced various conflicts and changes in governance, particularly during the Thirty Years' War, which affected its stability and influence in European affairs.