The Duchy of Jülich-Berg was a historical territory located in what is now western Germany. It emerged in the late Middle Ages and was known for its strategic position along trade routes. The duchy was formed from the union of the Duchy of Jülich and the County of Berg in the 15th century, becoming a significant political entity in the region. Throughout its history, the duchy experienced various conflicts and changes in leadership, particularly during the Thirty Years' War. It was eventually absorbed into larger states, notably the Duchy of Cleves and later the Kingdom of Prussia, marking the end of its independent status.