Germania Superior
Under Domitian, if not before, the Romans administratively separated the area of Treveran territory on the left bank of the Rhine from the "civitas Treverorum" and the province of Gallia Belgica, attaching the Rhenish Hesse region to the newly organized province of Germania Superior. The Aresaces were likely to have been organized as a separate "civitas" from the Treveri at this stage, if not earlier, as were their neighbours the Cairacates. Meanwhile, the city of Mainz—known in Latin as "Mogontiacum"—flourished as a legionary headquarters for a number of Roman legions and also the capital of the province of Germania Superior.