Who married Mathilde?

Simon III de Montfort (1117 – 13 March 1181), nicknamed the Bald (le chauve), was count of Évreux from 1140 until 1181 and the Seigneur of Montfort from 1137 to 1181. He was the son of Amaury III and Agnès de Garlande, daughter of Anseau de Garlande.