Royal Frankish Annals
The Royal Frankish Annals mention a 743 Frankish campaign led by the Carolingian Mayor of the Palace Carloman against the Saxons, followed by a second expedition together with his brother Pepin the Short the next year. In 747 their rebellious brother Grifo allied with Saxon tribes and temporarily conquered the stem duchy of Bavaria. Pepin, Frankish king from 750, again invaded Saxony and subdued several Westphalian tribes until 758.