The Domain of Soissons was a Carolingian lordship in the ninth century.
The city of Soissons served as its capital. The domain was located in the northern part of the kingdom of France, and its lord was a vassal of the king.
The first known lord of Soissons was Adalard, who served King Charles the Bald (r. 843-877). Adalard was a powerful nobleman and held several other important positions in addition to his lordship over Soissons. He served as seneschal (a royal official responsible for administration) of Neustria (the western part of the kingdom), and he also held lands in Burgundy and Italy. In 867, he participated in an expedition against Viking raiders that sacked Paris.
Adalard’s son, Arnulf I (r. 877-884), succeeded him as lord of Soissons.
Arnulf continued his father’s tradition of service to the crown, serving as missus dominicus (a royal representative sent on missions throughout the kingdom) and participating in military campaigns against Vikings and rebels. He expanded his family’s holdings by acquiring more land around Soissons.
Arnulf’s son, Berengar II (r.884-888), inherited the domain upon his father’s death but did not hold it for long; he died fighting Viking raiders near Amiens in 888.
His brother Odo I (r.,888-898) then became lord of Soissons; like his predecessors, he served King Charles III (Charles the Fat; r., 879-887) faithfully, even though Charles had been deposed by some nobles in 887 and replaced with Odo’s own cousin Carloman II (r.,887-889). When Carloman died suddenly in December 889, leaving no heir, Odo supported Charles’ return to power instead of backing another candidate for kingship such as Duke Rudolph II of Burgundy or Count Guy III of Spoleto.
For this loyalty Charles rewarded Odo by making him dux Francorum (“duke [or leader]of Franks”; i .e., commander in chief of all Frankish forces), a position that made him one of the most powerful men in the realm.
Odo used his new position to expand his family’s holdings even further; he acquired additional land around Soissons as well as the county of Laon, which increased his family ‘s prominence and wealth considerably.
He also continued to serve Charles loyally during the latter’s years as king, although his position waned somewhat after Charles’ deposition by Hugh Capet in 987. After Odo’s death in the same year, his lands were divided between his two sons: Baldwin II received Soissons and its environs while Herbert I was given Laon. Both brothers continued their ancestors’ tradition of fidelity to the crown: Baldwin served King Robert II (r .” 996 -1031) faithfully during his campaigns to subdue rebels in Normandy while Herbert fought against invading Viking forces under Cnut the Great at Val-ès -Dunes near Caenin 1047.