The "Duke of Milan" refers to the title held by the rulers of the Duchy of Milan, a significant state in northern Italy during the Renaissance. This title was often associated with powerful families, such as the Visconti and Sforza, who played crucial roles in the political and military affairs of the region. The Duchy of Milan was known for its wealth, cultural achievements, and strategic location. It became a center for art and innovation, attracting notable figures like the artist Leonardo da Vinci and the architect Donato Bramante. The title of Duke was often contested, leading to various conflicts and alliances throughout history.