The house of Namur is a family of the Lotharingian nobility, coming from Berenger count of Lommegau. He later became count of Namur, when the county of Lammegau was renamed to county of Namur. He married a sister of Giselbert duke of Lotharingia, from the House of Reginar. Vita Gerardi abbatis Broniensis states that the descendants of Berenger continued to hold the county of Namur, but the relationship between Berengar and his successor Robert I is not known. Some think that Robert is a grandson of Berengar by his mother, others speak of a nephew.