Rotrou III, called the Great, was the Count of Perche and Mortagne from 1099. He was the son of Geoffrey II, Count of Perche, and Beatrix de Ramerupt, daughter of Hilduin IV, Count of Montdidier. Wikipedia
Born: 1080
Died: May 8, 1144 (age 64 years), Rouen, France
Spouse: Matilda FitzRoy, Countess of Perche (m. 1103)
Parents: Geoffrey II, Count of Perche
Children: Rotrou IV, Count of Perche and Stephen du Perche
Great grandchildren: Thomas, Count of Perche, Alix d'Alençon, Helie d'Alençon, and more
Great-grandparents: William of Bellême, Mathilde, Dame de Condé-sur-Noireau, and Guerin de Bellême, Seigneur de Domfront