Vandals, Alans, Suevi, Alamans

Towards the end of the year 406, a large armed band of men consisting of Vandals, Alans, Suevi (probably the Quadi branch of the tribe), and others, launched an attack on Rhaetia from the mid-Danubian region. Forced back by Stilicho, the army turned towards the Main basin, where it devastated the territories of the Alamans and was swelled by yet more Vandals and also Burgundians. While still east of the Rhine, the invading army was stoutly resisted by Frankish federati but nevertheless managed to cross the river on 31 December 406 into the province of Germania Prima.

With Stilicho fighting Alaric in Italy, it fell to the usurper Constantine to defend Gaul, using legions withdrawn from Britain. But Constantine was attacked and halted close to Aries by imperial troops who preferred - not for the first or last time – to wage civil war rather than defend the empire against an external enemy. Except for the Burgundians, who spread along the River Main to the cost of Alamanic tribes, the bulk of the invaders moved slowly through Gaul, eventually halting in the Iberian peninsula in the autumn of 409 after an unimpeded crossing of the Pyrenees made possible by the defection of the frontier troops, who joined the invaders.