Arnold I, Count of Loon
In 1088, he spoke on the request of Bishop Henry of Verdun to end a conflict in the Abbey of St. Truiden where the bishop and emperor Henry IV had both appointed a successor abbot. As a result of his diplomacy, the emperor transferred the authority of the abbey of Sint-Truiden from Henry I, Duke of Lower Lorraine, to Arnold. Arnold forced Henry and his ally Godfrey of Bouillon, to withdraw from the monastery. The domain of Arnold expanded with the County of Rieneck by his marriage to Agnes.
Arnold married Agnes von Mainz, daughter of Gerhard I, Count of Rieneck, and Helwig von Bliescastel. Sources disagree on their number of children, but are believed to include:
- Gerard? (d. 1103, but probably did not exist). Count of Loon for a brief period according to the old Belgian National Biography, pointing to a charter of 1101. Baerten (1969 p.40 footnote 2) describes this as a mistake caused by modern edition with a wrongly placed comma, and gives references to the literature.
- Arnold II, Count of Looz. He is distinguished from his father of the same name by historians who note records for counts named Arnold or Arnulf between 1179 and 1141, which seems too long to be one person. The first Arnold must have died between 1125 when Count Arnold appears in a record with his son also named Arnold, and 1135, when a new Count Arnold appears with his own son and successor Louis.
- Gertrude van Loon (1100–1154), married to Hugo XI, Count of Dagsburg. Their son was Hugo XII, Count of Dagsburg, who married Luitgarde, widow of Godfrey II, Count of Louvain. She was daughter of Berengar II of Sulzbach, and sister of Gertrude von Sulzbach, wife of Conrad III of Germany, and Bertha, wife of Manuel I Comnenus, the emperor of Byzantium. Their granddaughter was Gertrude of Dagsburg, wife of Theobald I, King of Navarre.
- Agnes van Loon (born c. 1100), married Gerhard IV, Count of Jülich
- Beatrix van Loon (died after 1132), married Arnout III, Count of Aarschot and had issue.
While the confusion about the non-existent "Gerard" remains, Arnold is now understood to have been succeeded by his son Arnold as Count of Looz upon his death.
- See for example Baerten
- J.-J. Thonissen, "Arnoul Ier et Arnoul II", Biographie nationale de Belgique, vol. 1 (Brussels, 1866) link
- Vanderlinden, H., "Le tribunal de la paix de Henri de Verdun (1082) et la transformation de la principauté de Liège", in Mélanges Henri Pirenne, 1926
- Baerten, Jean (1969), Het Graafschap Loon (11de – 14de eeuw) (PDF)