The Countess of the Vexin refers to noblewomen who held the title of Countess in the historical region of the Vexin, located in northern France. This area was significant during the medieval period, often contested between the Duchy of Normandy and the Kingdom of France. The title was typically associated with land ownership and local governance. One notable Countess of the Vexin was Adelaide of Vexin, who lived in the 10th century. She was married to Hugh the Great, a powerful nobleman, and their descendants played crucial roles in the political landscape of France. The title has been held by various women throughout history, reflecting the region's importance.