The Duchess of Rethel was a noble title in the historical region of Rethel, located in present-day France. This title was often held by women who were married to the Duke of Rethel or were members of the royal family. The duchy played a significant role in the feudal system, contributing to the political and social landscape of medieval France. The title of Duchess of Rethel is associated with various historical figures, including Marie de Rethel, who was notable for her marriage alliances that strengthened political ties. The duchy itself was part of the larger County of Rethel, which was influential during the Middle Ages.