The Duke of Brabant was a historical title associated with the region of Brabant, which is now part of modern-day Belgium and Netherlands. The title emerged in the 11th century and was held by various noble families, most notably the House of Reginar and later the House of Habsburg. The Duke of Brabant played a significant role in the political landscape of medieval Europe, often engaging in alliances and conflicts with neighboring territories. The title of Duke of Brabant was officially abolished in the 18th century, but its legacy continues in the cultural and historical identity of the region. Today, the title is often referenced in discussions about the history of Belgium and the development of its provinces. The last Duke of Brabant was Leopold II, who became King of the Belgians.