The Counts of Duras first appeared in the 11th century and are of unknown origin. The counties of Duras, Grez and Aarschot developed in the 11th and 12th centuries in the area of the former county of Hesbaye. These nobles eventually merged with the Counts of Loon. See the main article, Counts of Hesbaye.
The name of the first Count of Duras is unknown. His wife, Herlendis (d. after 2 November 1023) was Countess of Duras and of unknown parentage. Her name appears in various donations, including one noted by Henry II of Leez, Prince-Bishop of Liège, in 1164. Herlendis and her husband had three children:
Adalbero did not inherit the title of count, and so it is speculated that his father was perhaps the first husband of Herlendis.
Nothing is known about the next count, Godefroi, other than various donations in his mother’s name.
Presumably, Godefroi was succeeded as Count of Duras by his brother Giselbert, who is frequently confused with Giselbert, Count of Looz. Giselbert was the under-voogde of Saint Trudo’s Abbey, named after Saint Trudo, the apostle of Hesbaye. Giselbert is known as Giselbert I to distinguish him from his grandson Giselbert II, also Count of Duras.
Giselbert and his wife (name unknown) had at least one child, a daughter:
Oda inherited the county of Duras, and her husband Otto became Count of Duras by marriage. She also became guardian (vogt) of the abbey which was financially exploited by both the Dukes of Limburg as well as successor Counts of Duras.