The Pannonian revolt broke out in AD 6. Tiberius had been engaged in an expensive programme of conquests. His armies had crossed the Elbe, returning to where his brother had reached, but had also defeated tribes seemingly north of the Danube.
Over the previous decades the Romans had extended their control from the coastal regions of the Balkans, which is modern Croatia and Albania, to the north and east. The detailed geographical course of the campaigns cannot be reconstructed, perhaps in part because the conquest itself caused the relocation of settlements or because the Romans did not carefully record the settlements through which they marched. By AD 6, the Romans seem to have extended their control along much of the southern bank of the Danube.
Velleius Paterculus, 2. 110 gives the number of persons (which might be men or the total population) who rose up against Rome as 800,000, though how he could know that number is unclear. Dio, 55.29 puts the revolt down to three causes:
- The tribute being levied on the Dalmatians.
- The absence of the governor who was leading his army in support of Tiberius’s expansion in Germany.
- The levies of Dalmatian troops secured to support the war effort in Germany.
The Romans had traditionally made use of recently pacified groups to support the next stage of their military efforts. The practice of levying troops and tax the Dalmatians suggests that they were now confident in their control over the region. However, in many regions, the imposition of Roman taxation and infrastructural arrangements associated with tax (counting people, measuring land, requiring payments in money or kind) and in levying soldiers (often a forced levy) led to resistance.
The Dalmatians were a tribal society with a fragmented political structure. Such fragmentation into small communities aided Roman conquest. But the Roman administrative processes brought together political and military leaders and concentrated the levies in one place ready to march to Germany. Such a concentration of strength encouraged the levies to believe that success might be possible and they revolted.
The first stage of the revolt was led by a local king called Bato. Bato raised his tribe and they defeated the Roman forces sent against them. Once they saw that there was a chance of success, the other tribes joined them. Almost immediately a Pannonian tribe, also led by a king called Bato, also took up arms. United, the tribes of the province thought they might win (Dio, 55.30). Troops were brought in from Germany, Moesia and Thrace and in paradoxical account Dio suggests that the Romans won various battles, but retreated, and far from put off by their repeated defeats, the Pannonian-Dalmatia allies raided into Macedonia. Velleius Peterculus (2.112) gives us an account of a victory, which looks very like a defeat, in which a five legion army was beset by the Dalmatians. Typically, it seems as though the Roman generals exaggerated their successes and minimised their defeats.
The true extent of the problem is indicated by the Romans’ actions. Augustus raised a new army in Rome, an army raised from a levy of free citizens and also of freedmen, who were normally excluded from the army. These troops were not organised into legions, but remained in cohorts of about 500 men. It was an emergency levy suggesting that Rome’s resources of manpower were stretched to the limits and that many Romans were reluctant to serve. Terms of service were probably 16-20 years and the revolt in Pannonia suggested that the chances of being killed on service were quite high (Dio, 55.31-32; Velleius Paterculus, 2.111).
The initial ‘successes’ led to Tiberius concentrating a huge army in a single location to attack the Dalmatians and Pannonians. The force is listed in Velleius Paterculus, 2.113 and numbered at least 102,000 men. Rome’s total military force can be guessed at (28 legions and a similar number of allied troops) between 240,000 and 300,000. But to put more than 100,000 in one area was massive logistical effort. It also suggests that Tiberius wanted to over-awe the rebels. Rome’s tactics had previously been to employ smaller, more mobile armies who would strike into enemy territory from different directions, but it seems as though these smaller armies had risked defeat. Now Tiberius appears to have adopted a more cautious approach. This huge army progressed, inevitably slowly through hostile territory, while smaller armies, under the command of other generals, struck rapidly into enemy territory. The rebels were faced with an army so large that they could not defeat it, but also with forces that could ravage their territories and attack their towns.
Tiberius avoided battles. His tactics were to wear down his opponents and reduce them by attrition and destruction of their land. Under such pressure, the unity of the rebellion collapsed (Dio, 55.34). The war dragged on through AD 9, becoming increasingly a war of sieges as the Romans recovered territory, with Germanicus and Tiberius fully engaged (Dio, 56.11-16).
Eventually, the various tribes were brought to peace. Dio finishes his account with a description of the meeting of Bato and Germanicus. Bato complained that the revolt was caused by the Romans: they were wolves who ravaged their subject peoples, not shepherds who cared for them.
The war in Pannonia stretched Roman military resources. But the Romans responded with overwhelming force. They could concentrate their power on the rebels and maintained large armies in the field for years. Against this level of military organisation and the sheer scale of Roman military resources, the rebels had little chance.
After decades in which Roman power was extended through the Dalmatian and Pannonian region. the rebels can hardly have been surprised by the Roman response. The fact that they decided to fight when the odds were ultimately against them suggests that they thought that they had little choice. Better to fight than abandon themselves to the wolves.