 In 819, he and Berengar of Toulouse invaded Gascony to put down a rebellion of Lupus III Centule, as recorded by both the "Annales regni Francorum" and the "Vita Hludowici".By 820, Gascony was pacified and Carolingian authority restored, but not across the Pyrenees in Navarre.On 24 July 840 in Strasbourg, Lothair precipitated a new civil war by declaring his "imperium" over all the lands of the empire and, joining with his nephew Pepin II of Aquitaine, attacked the Loire Valley.