Baldwin IV, Count of Hainaut

Baldwin IV (1108 – 8 November 1171) was count of Hainaut from 1120 to his death.

Baldwin IV was the son of Count Baldwin III of Hainaut and Yolande de Wassenberg. Also known as Baldwin the Builder, he purchased the property of Ath in 1158 and built the Burbant tower. He ceded the locality of Braine-la-Willotte, also known as Braine-le-Comte, to the chapter of Sainte-Waudru in 1158. In 1159, he incorporated the seigniory of Chimay and in 1160 the châtellenies of Valencians and of Ostrevent. Children Baldwin IV married Alice, Geoffrey, Count of Ostervant (1147–1163), first husband of Eleanor, Countess of Vermandois Lauret(t)a (1150–1181), married first to Thierry of Alost, and second to Bouchard V, Count of Montmorency Baldwin V (1150–1195), also count of Flanders by his marriage to Margaret I of Flanders.