Overview
Giselbert van Loon (probably died about 1045) is the first definitely known count of the County of Loon, a territory which, at least in later times, roughly corresponded to the modern Belgian province of Limburg, and generations later became a lordship directly under the Prince-bishopric of Liège. Very little is known about him except that he had two brothers, one of whom, Bishop Balderic II of Liège, is much better attested in historical records.
Origins
Giselbert's parents are not known for sure. A 14th century writer of the Gesta (chronicle) of the Abbey of St Truiden states that the parents of Giselbert and Balderic were Count Otto of Loon (otherwise unknown) and his wife Liutgarde, daughter of Countess Ermengarde of Namur, who was a daughter of Duke Otto of Lower Lotharingia. However, there are doubts about the reliability of this much later source. (For example, other records confirm that Countess Ermengarde was a sister of Duke Otto, not a daughter.)
In contrast to the chronicle continuation, it was proposed by Joseph Daris (in 1896), and Léon Vanderkindere (in 1900), that Giselbert is likely to be son of Rudolf, whose mother was a daughter of Count Reginar II, and father was Count Nevelong. This Rudolf, known from a 943 record, when he was still a boy, was the younger brother and nephew of two bishops named Balderic: Balderic I of Liège and Balderic of Utrecht. Because of the very big gap in generations, two proposals have been made in which Otto, Count of Looz is accepted as father of Gilbert, but in a way which makes him Nevelong's grandson, adding a generation:
J.M. Winter proposed that Otto was a son of Rudolf.
Jongbloed proposed that Otto was son of Bertha, the mother of Count Arnoul of Valenciennes, who Vanderkindere long ago proposed to be a sister of Rudolf.
In medieval records, Bishop Balderic II of Liège, about which more was written than his brothers, was said to be a kinsman of both Lambert I, Count of Louvain and Arnoul of Valenciennes. According to Kupper, he may have also had common ancestry with Bishop Gerard of Florennes.
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