Count Giselbert (or Gilbert) of Loon or (later) Duras (d. before 1138), was the deputy advocate (subadvocatus) of Saint Trudo’s Abbey.
Apart from the Gesta, much of what we know about Giselbert is from the charters that he witnessed, which also gives insight as to his relationship with the Counts of Namur, a family into which he eventually married.
[clarification needed] Emperor Henry IV confirmed donations made by Henry I, Count of Durbuy, son of Albert II, Count of Namur, to the Church of Saint James in Liège, as witnessed by Giselbert.
The emperor also confirmed the claim of Albert’s family to Saint Begga's Collegiate Church in Andenne.
Giselbert and Gertrud had eight children: Wolters identifies Julienne, daughter of Otto II, as an additional daughter of Giselbert and Gertrud, but this is unlikely as her husband and their sons inherited the countship of Duras.