The physical absence of the Carolingian army coupled with the news of their defeat led to the insurrection of other subjugated peoples. King Charles’ defeat in the extreme south of the kingdom stimulated Widukind’s uprising in Saxony and, quite possibly, it also fueled the political upheaval in Aquitaine and Lombardy. The Enhardi Fuldensis Annales records that Widukind's uprising proved particularly bloody and resulted in the destruction of Karlsburg ‘by iron and fire’. And the repression was likewise brutal, with episodes of massive killings and deportations of population over the course of several punitive military campaigns until the submission and baptism of the Saxon leader in 785.

As Francois-Louis Ganshof has indicated, the disaster of Errozabal abetted the revolt in Saxony and produced a critical situation, from both a purely military perspective as well as from a political and economic one.

As regards the economic consequences, the booty obtained from looting was one of the principal motivations for the Frankish annual military campaigns. As sources attest, the cost of the emperor's unsuccessful campaign fell on the royal coffer which was unable to count on the spoils of war. The sources record that upon his return to Herstal, the emperor had to face the additional economic burden of organizing a new army. We know also that on his way to Herstal he passed through Paris, most probably to stop in Saint- Denis and pay a visit to Abbot Fulrad, advisor of Pepin and Charlemagne from at least 750 until his death in 784.