In 405 the Vandals advanced from Pannonia travelling west along the Danube without much difficulty, but when they reached the Rhine, they met resistance from the Franks, who populated and controlled Romanized regions in northern Gaul. According to the Frigeridus fragment cited by Gregory of Tours, around 20,000 Vandals, including Godigisel himself, died in this Vandal-Frankish war, but then with the help of the Alans they managed to defeat the Franks, and on December 31, 405 the Vandals crossed the Rhine, probably while it was frozen, to invade Gaul, which they devastated terribly. Under Godigisel's son Gunderic, the Vandals plundered their way westward and southward through Aquitaine.