The Duchy of Hainaut was a historical region located in present-day Belgium and France. It emerged in the 14th century and was part of the larger County of Hainaut, which was known for its rich agricultural land and strategic location. The duchy played a significant role in the political landscape of medieval Europe, often changing hands through marriages and treaties. Hainaut was ruled by various noble families, including the House of Valois and the House of Habsburg. The duchy was known for its cities, such as Mons and La Louvière, which contributed to its economic development. Over time, it became integrated into larger political entities, eventually becoming part of the Burgundian Netherlands.