There are no contemporary sources about Widukind's life or death after his baptism. Historian Gerd Althoff assumed that he was imprisoned at a monastery—a fate that happened to other rulers deposed by Charlemagne. He tried to identify Reichenau Abbey as a likely location where Widukind may have spent the rest of his life, but his results are inconclusive and widely rejected. Alternatively, he may have received a position in the administration of occupied Saxony. The "Vita Liudgeri" biography of Saint Ludger mentions him accompanying Charlemagne on his campaign against the Veleti leader Dragovit. According to the 12th-century "Kaiserchronik", he was slain by Charlemagne's brother-in-law Gerold of Baar.