Richilde, Countess of Mons and Hainaut (c. 1018 – 15 March 1086). She was also Countess and Regent of Flanders.Richilde was either the daughter or the daughter -in law of Regnier V Count of Hainault . She was born c. 1018. She was married firstly to Herman of Mons who was Count of Hainault. (Count of Hainaut), c. 1040. After the death of Herman, Richilde married Baldwin, eldest son of Baldwin V of Flanders.