The Dukes of Saxe-Gotha were a line of German noble rulers from the House of Saxe-Gotha, which emerged in the 17th century. The duchy was part of the larger region of Saxony and was established in 1640. The dukes played a significant role in the political and cultural life of the area, promoting arts and education. The most notable duke was Ernst I, who ruled from 1640 to 1675 and was instrumental in developing the duchy. The line eventually merged with other noble houses, leading to the formation of the Duchy of Saxe-Coburg and Gotha in the 19th century, which further influenced European royalty.