Research Notes:

Died maybe after 6 Sep 885.

Giselbert's origin is unknown. However, Viking connections are suggested by his supposed son's name, similar to the Nordic "Ragnar", especially bearing in mind the increasing number of Viking raids south of Frisia after [825/30] and Frankish concessions of territory in the low countries to Danish leaders. Another possibility is that Giselbert was related to Reginar [Reginhere] son of Meginhere.

Graf von Maasgau. Nithard names "Giselbert count of the Maasgau" ("comes Mansuariorum") as one of the supporters of Charles II "le Chauve" King of the West Franks against his half-brother Emperor Lothaire. He was obliged to leave his county, attributed to him by Emperor Lothaire after the treaty of Verdun in 843. Giselbert supported Pépin King of Aquitaine, but after the latter fell from power found refuge with Ludwig II "der Deutsche" King of the East Franks. He abducted and married Emperor Lothaire's daughter without her father's consent (see below), but was finally pardoned by the emperor in 849 and authorised to return to his lands. An agreement between Charles II "le Chauve" and his brother Ludwig II "der Deutsche" dated Jun 860 names "nobilis ac fidelibus laicis…Gislebertus…".

Comte in Darnau: "Ansfridus…comes…et Hildiwardus filius meus" donated property "in pago Darnau, in marca vel villa Sodoia…super fluvium Geldiun, in comitatu Giselberti" to Lorsch by charter dated 5 Oct 863. An agreement dated 14 Jun 877 of Emperor Charles II "le Chauve", presumably written with his own death in mind, names "Arnulfus comes, Gislebertus, Letardus, Matfridus, Widricus, Gotbertus, Adalbertus, Ingelgerus, Rainerus" as those willing to support the emperor's son if he travels across the Meuse. Emperor Karl III granted property "in pago Condruscio…Alnith" to "Gislebertus…comes…fidelis suis Teodone" by charter dated 6 Sep 885. ¹