 Valentinian spent the entire winter of 367 gathering a massive army for a spring offensive.He summoned the "Comes Italiae" Sebastianus, with the Italian and Illyrian legions, to join Jovinus and Severus, the "magister peditum".In the spring of 368 Valentinian, his eight-year-old son Gratian and the army crossed the Rhine and Main rivers into Alamannic territory.