Duke William I of Jülich was a nobleman who ruled the Duchy of Jülich in the late 15th century. He was born in 1467 and became Duke in 1511, known for his efforts to strengthen the duchy's political and economic position in the region. His reign was marked by alliances and conflicts with neighboring territories. William I was also a member of the House of Jülich, a prominent noble family in the Holy Roman Empire. He played a significant role in the politics of North Rhine-Westphalia and was involved in various military campaigns, contributing to the history of the area during the Renaissance period.