Pannonia
Pannonia was a province of the Roman Empire bounded on the north and east by the Danube, on the west by Noricum and upper Italy, and on the south by Dalmatia and upper Moesia. It included the modern regions of western Hungary, western Slovakia, eastern Austria, northern Croatia, north-western Serbia, northern Slovenia, and northern Bosnia and Herzegovina. The northern and eastern boundary line of Pannonia was formed by the River Danube.
Background
In the Early Iron Age, Transdanubia was inhabited by the Pannonians or Pannonii, a collection of Illyrian tribes. The Celts invaded the region during the Late Iron Age, and Gallo-Roman historian Pompeius Trogus wrote that they faced heavy resistance from the locals, which eventually prevented them from overrunning the southern part of Transdanubia. Some tribes advanced as far as Delphi, with the Scordisci settling in Syrmia upon being forced to withdraw. Additionally, the arrival of the Celts in Transdanubia disrupted the flow of amber from the Baltic Sea region, through the Amber Road, to the Illyrians. They founded many villages. Those that held prominent economic significance developed into oppida. Independent tribes minted their own coins with the faces of their leaders. These were at first modelled on Macedonian and, later, Roman currency.Upon the Scordisci's withdrawal and settlement, they and the Dardani both became strong powers that opposed each other. The Dardani consistently raided Macedon and developed close ties to Rome. Philip V of Macedon, who was a vehement enemy of the Dardani, allied with the Scordisci and, in 179 BC, persuaded the Bastarnae to break into Italy and subdue them on the way. Despite Philip's defeat at the hands of the Romans in 197 BC and the failure of the Bastarnae, at this time the Dardani's power crumbled under the pressure from the Macedonians and Scordisci. Finally, Perseus annihilated them, giving way to a hundred years of Scordisci hegemony in the Balkans. During this time, the tribe started raiding the new province of Macedonia, and —Strabo says— expanded as far as Paeonia, Illyria, and Thrace.
Aquileia's foundation in 181 BC was the first step towards the Roman takeover of Pannonia. The town served as the starting station of the Amber Road and the launching point for attacks in that direction. The Scordisci, in alliance with the Dalmatae, were in armed conflict with the Romans as early as 156 BC and 119 BC. In both wars, the Romans failed to conquer Siscia, which laid in a key position. After these setbacks, Rome turned its attention to Noricum, which had both iron and silver mines.
As part of a new Celtic migration wave at the end of the 2nd century BC, the Boii left Northern Italy and established themselves as a significant power on the Danube. According to Posidonius's record of the Cimbri migration, they were first repulsed by the Boii, then by the Scordisci, and then by the Taurisci towards the Helvetii. This describes the balance of power in the region. In the early 1st century BC, the Dacians emerged as a new dominant power. While their hold on the area between the Danube and the Tisza river was loose, they had considerable influence in the territories beyond. In 88 BC, Scipio Asiaticus defeated the Scordisci so badly that they retreated to the eastern part of Syrmia. Taking advantage of this situation, the Dacian king Burebista vanquished them sometime between 65 and 50 BC, and subsequently the Boii and the Taurisci too. Thanks to the ebb of these entities, several local tribes regained their independence and influence. In the context of Mithridates VI Eupator's unfulfilled plan to invade Italy from the north, the territory he was to cross is noted to have belonged to the Pannonians. Immediately after Burebista's death, Dacia's kingdom dissolved too, leaving no entity in the region that Rome would make allowances for.
Roman conquest
The Pannonians were driven into conflict due to their support of the Dalmatae in their strife against Rome, but they weren't long-term and known enemies. The tribes north of the Drava River didn't participate in this, nor in the subsequent fights. In 35 BC, Octavian led a campaign against the Iapydes and the Pannonians, in which he captured Siscia in a month-long siege and occupied a large part of the Sava River valley. This was in accordance with Caesar's plan of creating a base for an invasion of Dacia, not realized due to his assassination. However, Octavian only used the hoax of the "Dacian threat" as a pretense to gain control over a large amount of land in the Second Triumvirate.In 15 BC, the future emperor Tiberius defeated the Scordisci, forcing them to become allies. This was in response to Pannonian and Scordisci incursions the previous year. The following events were part of the Roman Empire's efforts to reach the Danube and are sometimes known thematically as Bellum Pannonicum.
In 14 BC, the Pannonians rose up. Vipsanius Agrippa was sent to the region after another rebellion in 13 BC. After his death the following year, the campaign was taken over by Tiberius, who celebrated his triumph in 11 BC. The province of Illyricum was established between the Sava and the Adriatic Sea. In 10 BC, Tiberius returned to quell a new uprising of the Pannonians and Dalmatae. After winning in 9 BC, he sold the youth of the Breuci and Amantini as slaves in Italy and held an ovation. His operations between 12 and 9 BC included constant expeditions into territories north of the Drava and almost certainly brought the whole Transdanubia under Roman control, even though there's no direct evidence for that.
Pannonia was invaded by the Dacians in 10 BC. The Romans launched campaigns through the Danube in order to secure it as the imperial border and defend the threatened new land. Lucius Domitius Ahenobarbus's operation in 1 AD extended as far as the Elbe. In 10 AD, Cornelius Lentulus Augur was able to debar not just the Dacians, but also the Sarmatians "from access to the Danube", says Florus. Locally more important was the offensive of Marcus Vinicius against the tribes east of the Danube Bend, showing an intent of "monopolizing" the Northern Transdanubian region politically. The last decade of the century saw the Marcomanni under their king Maroboduus, settling north of Pannonia. Augustus planned a two-sided attack on them, with one army approaching their territory from the Rhine and another one under Tiberius crossing the Danube at Carnuntum.
Before witnessing any result, Tiberius had to rush back in 6 AD and face a new uprising. The unfolding Bellum Batonianum lasted for three years. The Breuci and Daesitiates took the leading role, while the tribes north of the Drava stayed out again. The insurgents attempted to invade Italy and Macedonia, but due to their lack of success, they united to besiege Sirmium. There, Caecina Severus defeated the insurgents, who retreated into the Fruška gora Mountains. He annihilated them the following year when they tried to intercept him on his way to join Tiberius at Siscia. Tiberius competently initiated a scorched-earth policy which was unsatisfactory for Augustus, who sent more generals, including Germanicus and Plautius Silvanus to the war theatre. A capitulation was forced out in 8 AD, and Bato the Breucian delivered Pinnes to the Romans, becoming a vassal king of his tribe. However, the revolt flared up once again as the Daesitiates captured and executed Bato the Breucian and persuaded his people to continue the resistance. Silvanus reconquered them and ousted Bato the Daesitiate into the Dinaric Alps, where he laid down arms in 9 AD.
History
Consolidation and establishment of administration
Illyricum was divided into Dalmatia and Pannonia in 8 or 9 AD.According to Suetonius, with the Bellum Batonianum, Tiberius finally defeated all peoples between the Danube and the Adriatic Sea. No Illyrian resistance is known after this, not due to the natives' compliance with the new status quo, but due to their extreme exhaustion. The eligible Pannonian youth were conscripted and commanded to other provinces. The communities taking part in the uprising were afterward relocated and organized into civitates under military supervision.
The military occupation of Pannonia may have been carried out in gradual steps. The Romans felt it necessary to resettle certain tribes to the territory of the peoples north of the Drava, which, for them, had no economic, but strategic significance. Augustus formed a kind of alliance where the Romans would act as supervisors, and it was not until his death that legions would be moved over from South Pannonia.
The second emperor Tiberius founded multiple coloniae in the province and developed its road network. However, due to these land's unsuitability for cultivation, it was a hard task to persuade veterans to comply with settling there, and he had to silence a mutiny right when assuming power. He sent his son Drusus Julius Caesar to create tranquility and depose Maroboduus, who needed Roman support for his war against Arminius. This ultimately caused the rise of Vannius, who ruled over an extended realm.
It was Claudius who finished Pannonia's occupation and began to construct of the local limes. Systematic integration into the Empire accompanied by the establishment of settled Roman life progressed subsequently. In 50 AD, Vannius was overthrown by Vangio and Sido, who enjoyed the emperor's support. By this date, the nomadic Sarmatian population of the Iazyges had taken possession of the Danube–Tisza Interfluve, helping the Romans by being a buffer state against the dangerous Dacians.
At first, the primary goal of the Roman administration was the conclusion of the barbarian conflicts outside the province. In Nero's time as many as 100,000 barbarians were moved from Pannonia to Moesia by Plautius Silvanus Aelianus, and 50,000 may have been settled in Pannonia by Tampius Flavianus. During his important governorship, money began to circulate in the Barbaricum and the line of the limes was stabilized.