William III, Duke of Aquitaine was a prominent nobleman in the 10th century, known for his significant influence in the region of Aquitaine in southwestern France. He was a member of the powerful House of Poitiers and played a crucial role in the political landscape of medieval France, often engaging in alliances and conflicts with other noble families. As Duke, William III managed vast lands and resources, contributing to the economic and cultural development of Aquitaine. His reign was marked by efforts to strengthen his authority and expand his territory, which laid the groundwork for future generations of dukes in the region.