Guy de Montlhéry was a notable figure in medieval France, known for his role as a nobleman and military leader. He lived during the 10th century and was part of the influential Montlhéry family, which held significant lands in the Île-de-France region. His lineage is often associated with the early development of the French nobility. He is particularly recognized for his involvement in the political and military conflicts of his time, including battles against rival factions. Guy de Montlhéry played a crucial role in the power struggles that shaped the landscape of feudal France, contributing to the establishment of noble alliances and territorial control.