>>17836639 (OP)"Meanwhile it befell that Karl, King of the Franks, crushed Germany in war, and forced it not only to embrace the worship of Christianity, but also to obey his authority. When Gotrik heard of this, he attacked the nations bordering on the Elbe, and attempted to regain under his sway as of old the realm of Saxony, which eagerly accepted the yoke of Karl, and preferred the Roman to the Danish arms. Karl had at this time withdrawn his victorious camp beyond the Rhine, and therefore forbore to engage the stranger enemy, being prevented by the intervening river. But when he was intending to cross once more to subdue the power of Gotrik, he was summoned by Leo the Pope of the Romans to defend the city.
Obeying this command, Karl intrusted his son Pepin with the conduct of the war against Gotrik; so that while he himself was working against a distant foe, Pepin might manage the conflict he had undertaken with his neighbour. For Karl was distracted by two anxieties, and had to furnish sufficient out of a scanty band to meet both of them. Meanwhile Gotrik won a glorious victory over the Saxons. Then gathering new strength, and mustering a larger body of forces, he resolved to avenge the wrong he had suffered in losing his sovereignty, not only upon the Saxons, but upon the whole people of Germany. He began by subduing Friesland with his fleet."
-Gesta Danorum, 12th century
