The Dukes of Saxe-Lauenburg were rulers of a historical duchy located in northern Germany. This duchy was part of the larger region of Saxony and existed from the late Middle Ages until the early 19th century. The dukes played a significant role in the political landscape of the Holy Roman Empire and were involved in various territorial disputes and alliances. The most notable duke was Ernest I, who ruled in the 16th century and helped to establish the duchy's influence. Over time, the duchy was divided and eventually absorbed into other territories, particularly into the Kingdom of Hanover and the Duchy of Schleswig. The legacy of the Dukes of Saxe-Lauenburg continues to be of interest to historians studying the region's complex history.