The Duchy of Brabant was a historical region in what is now Belgium and parts of the Netherlands. Established in the 11th century, it became a significant political and economic center in medieval Europe. The duchy was known for its prosperous cities, such as Brussels and Antwerp, which played vital roles in trade and culture. Throughout its history, the Duchy of Brabant was ruled by various noble families, including the House of Reginar and later the House of Habsburg. In the 16th century, it became part of the Spanish Netherlands, influencing its political landscape until the region's eventual incorporation into modern Belgium.