The Vandals under king Godigisel, along with…

The Vandals under king Godigisel, along with their allies (the Sarmatian Alans and Germanic Suebians) had moved westwards into Roman territory in 400 or 401, possibly because of attacks by the Huns.

Some of the Silingi had joined them later.

Vandals had raided the Roman province of Raetia in the winter of 401/402.

From this, historian Peter Heather concludes that at this time the Vandals were located in the region around the Middle and Upper Danube.

Cultivation of rye, oats, hops, and spelt (a wheat used for livestock feed) is introduced into Europe by the invading Vandals, Alans, and Scirii, who also introduce a heavy wheeled plow to be used for farming.

The Vandals in 401 advance from Pannonia traveling west along the Danube without much difficulty, but when they reach the Rhine, they meet resistance from the Franks under Marcomir, who populate and control Romanized regions in northern Gaul.

Twenty thousand Vandals, including Godigisel himself, die in the resulting battle, but with the help of the Alans, they then manage to defeat the Franks, and on December 31, 405 (or 406) the Vandals supposedly cross the Rhine, probably while it is frozen, at Mogontiacum (modern Mainz), beginning an invasion of Gaul.