Lambert (ca. 903-after 960), Count of Louvain, Toxandrie and Maasgouw. A number of intriguing historical references imply that Lambert was from the House of Reginar and related to Robert, Archbishop of Trier. Details are provided in the discussion below.
Nothing is known about Lambert except that he was Advocate of Gembloux Abbey. His date of death is estimated on the basis that this entry in a manuscript Catalogo Abbatum Gemblacensium that indicates that Lambert had relinquished the advocacy of Gembloux in favour of his son, who must therefore already have been adult at the time.
Lambert married Herwesindis, a daughter of Ricfried, Count of Betuwe, and Herensinda. They were the parents of:
The biography of Balderic of Utrecht identifies him as a cousin of Gilbert, Duke of Lorraine, son of Reginar I, Duke of Louvain, implying that Lambert was Gilbert’s brother or half-brother. In addition, an account by the 18th century historian Miræus (see Vanderhindere) claims that Lambert was the son of Ragineri I et Alberadæ, frater Ragineri II Longicolli, Hannoniæ comitis [son of Ragineri I Longneck and Alberade, and brother of Reginar II, Count of Hainaut] although there are no primary sources to support the basis for this statement.
Thietmar refers to the "paternal uncle [of Count Ansfrid, Lambert’s son], Robert, Archbishop of Trier”, implying a sibling relationship between Lambert and Robert.
There is clearly an onanistic relationship between Lambert and the House of Reginar, as the first official Count of Louvain, son of Reginar III, Count of Hainaut, was named Lambert. Also, Liethard, daughet of Reginar II, Count of Hainaut, married Herwesindis’ brother Nibelung, Count of Betuwe.