An officer of Frankish ancestry, Nevitta is first mentioned regarding a battle against the Alamanni who had been pillaging the region of Raetia in 357.
The Romans were led by Barbatio and Ammianus Marcellinus writes that "Nevitta, commander of a troop of cavalry and afterwards consul, was present and conducted himself manfully.
[2] When Julian decided to move against Constantius in a bid for power, Nevitta was one of his two generals, the other being Jovinus.
It was Nevitta's task to lead his army through Raetia and then guard the pass of Succi, thus protecting Julian's rear as the Caesar moved on to Constantinople.
"[4] When the emperor Julian set up a tribunal at Chalcedon to try those involved in the excesses of the previous government, Nevitta was appointed as one of the judges.