The Roman city already served as a river port and hub of road communications, of the Via Agrippa and side routes.[3] In 354 AD the Roman Emperor, Constantius II stationed the Roman 7th Army in Chalon (then called Cabyllona) for an invasion against the brother kings, Gundomadus and Vadomarius of the Alamanni. However, not having received supplies, the Roman troops revolted, and were pacified by the grand chamberlain Eusebius with money. In Late Antiquity the city had dwindled so much that a wall round it encircled fifteen hectares.[4]