Rome's Gothic Wars_ From the Third Century to Alaric - Michael Kulikowski [15]
The Accession of Diocletian
We get our first indication that authors of the fourth century had come to understand the connection between internal Roman dissension and barbarian invasion with reference to the death of Probus. As the historian Aurelius Victor put it, writing around 360: ‘all the barbarians seized the opportunity to invade when they learned of the death of Probus’.[21] In response, the new emperor Carus left his elder son Carinus in charge of the western provinces and led an army against the Quadi and Sarmatians on the middle Danube before launching the invasion of Persia during which he met his end – supposedly struck by lightning, perhaps the victim of assassination.[22] The accession of Diocletian at Nicomedia in 284 prompted the inevitable war against Carinus. The latter had restored the Rhine frontier in 283, but by marching east to face Diocletian he allowed new barbarian raids on the Gallic coast. Carinus was defeated and killed at the battle of the Margus in 285, and in that same year, the victorious Diocletian campaigned against the Sarmatians on the Danube. He also appointed a colleague in the imperial office, a fellow soldier named Maximian, who campaigned on the Rhine.[23]
This was a significant step and one with major repercussions for the longevity of Diocletian’s regime. By appointing a co-emperor with whom he was on good terms and who would regard him as his benefactor, Diocletian hoped to give himself the breathing space needed to secure his hold on the throne and prevent rival usurpers appearing in parts of the empire where he could not be himself. The plan worked to a degree, although it took time. Only the appointment in 293 of two caesars, or junior emperors, allowed Diocletian and Maximian to suppress several provincial revolts and secure the frontiers. The evidence of these efforts is visible all along the imperial frontiers, for instance in the so-called Saxon shore forts along the Channel and North Sea coasts of what are now England, France, Belgium and the Netherlands. More important for the history of Roman relations with the Goths is the Diocletianic programme of fortification along the Danube. This consisted both of brand new constructions, as at Iatrus, and also of enlarged and refurbished early imperial fortifications, as at Augustae and Oescus.
Diocletian and the Goths
Such improvements were not simply measures of passive self-defence – they were also bases from which imperial campaigns could be supplied and supported. Already in the 280s, Diocletian and Maximian showed a renewed imperial willingness to campaign beyond the frontiers, and Maximian’s general Constantius – his caesar after 293 – won several spectacular victories against Franks on the lower Rhine. Meanwhile, Diocletian campaigned on the Danube against Tervingi and Taifali, winning victories in 289 and again in 291. That campaign is significant for us because it marks the first appearance of the Tervingian name in Greek or Latin writing. Our source is a panegyric – a speech in praise of the emperor Maximian, delivered in Gaul in 291 – and it refers to the Tervingi as pars Gothorum, which is to say, a section of the Goths.[24] As we shall see in the following chapters, the Tervingi