They made Milan their home; and the empire was nominally divided between them, Gratian taking the trans-Alpine provinces, whilst Italy, Illyricum in part, and Africa were to be under the rule of Valentinian, or rather of his mother, Justina.
As soon as it was known that the armies of the East, Dalmatia and Illyricum had declared for Vespasian, Vitellius, deserted by many of his adherents, would have resigned the title of emperor.
In 39 6 he fought in Greece against the Visigoths, but an arrangement was effected whereby their chieftain Alaric was appointed master of the soldiery in Illyricum (397).
He thwarted the efforts of Alaric to seize lands in Italy by his victories at Pollentia and Verona in 402-3 and forced him to return to Illyricum, but was criticized for having withdrawn the imperial forces from Britain and Gaul to employ against the Goths.
But the feeling in Vespasian's favour quickly gathered strength, and the armies of Moesia, Pannonia and Illyricum soon declared for him, and made him in fact master of half of the Roman world.