Liber Historiae Francorum
Berthoald (died 622) was the Duke of the Saxons during the reign of the Frankish kings Chlothar II and his son Dagobert I, the last ruling Merovingians. He despised Frankish suzerainty and rebelled, but was defeated. His story is told in the "Liber Historiae Francorum" (727) and the "Gesta Dagoberti" (830s), both sources partial to the Merovingian kings.