The Duke of Jülich was a title held by the rulers of the Duchy of Jülich, a historical region in what is now western Germany. The duchy was established in the late Middle Ages and became significant due to its strategic location and resources. The dukes played a crucial role in regional politics and were involved in various conflicts, including the War of the Spanish Succession. The title of Duke of Jülich was often linked to other noble titles, such as the Duke of Berg and the Duke of Cleves. The region was eventually absorbed into larger states, and the title became obsolete in the 17th century. The legacy of the dukes remains in the cultural and historical heritage of the area.