by 360, julian had restored peace to gaul and reached a ceasefire with the alamanni in particular. this secured the local borders for a while. meanwhile, constantius was involved in a conflict against shapur ii of the sassanid empire, another phase of the roman–persian wars. he took advantage of the peace achieved by julian, sending orders that would transfer many officers and units from gaul to the persian borders. the petulantes, one of the units ordered to the eastern border, revolted and proclaimed julian to be their augustus. soon their cause was joined by the rest of the gallic troops. julian accepted his proclamation with some initial reluctance. the exact date of his proclamations in unknown, estimated to february or march, 360. helena served as his empress consort. she is mentioned being alive at the time of his proclamation in julian's "letter to the senate and people of athens".