In 811, he attempted, with the help of the Franks and Saxons, to restore his authority over the tribes of the Linones and the Bethenici, who had soon after Thrasco's death thrown off their dependence on the Obodrites.
The Saxon-Obotrite army, under the command of Missus Baldric of Friuli, was tasked with restoring Harald Klak to the throne.
[e][6] Refusing to submit to the emperor's orders, Slavomir simultaneously sent an embassy to the sons of the Danish king Gudfred, with whom he formed a military alliance.
Gudfred's sons sent a fleet up the Elbe, while the land forces of both the Obodrites and Danes plundered the bordering provinces.
In that year, due to loss of trust in Cedragus,[f] Louis the Pious again designated the exile as the prince of the Obodrites and allowed him to return.