When it comes to empires, bigger is not always better. Conquerors and emperors certainly act as though it is. But history reminds us that larger empires are harder to manage, and that they eventually crack under their own weight.
As was the case with Rome. For 400 years (c. 200 BC – 200 AD) the city expanded its control from a small area in central Italy east all the way to Syria and the Middle East, across North Africa, and throughout western Europe.
With such a vast area to control, progress and prosperity depended on the emperor and the state’s ability to keep the peace across the empire. Rome’s most notable achievements, mainly in construction and city building, came during times of internal peace brought on by a powerful emperor.
However, in the third century, the affairs of the Roman state took a turn for the worse. A crisis, aptly named the Crisis of the Third Century, shook the empire at its core and changed its course forever.
The Growing Challenge of Managing an Empire
Due to its size, Rome faced a number of challenges that made political stability more difficult in the third century than ever before.
The first was “barbarians,” the Roman name for the many Celtic and Germanic tribes living on or near the northern borders to the Roman empire. They routinely invaded Roman territory in search of their own place to settle or simply to pillage. Securing military control in these regions required a dedicated, sustained effort, and success was an effective way to win the love of the local people.
This brings us to the next big challenge facing a larger-than-ever Rome: the independence of the military.
Throughout Roman history, Roman generals have always wielded considerable power. Their actions on the battlefield, which they carry out in the name of Rome, can make them extremely popular. They can then use this popularity to win political support from the people.
However, as Rome expanded, the popularity of successful military generals became increasingly local. Their victories would win them the support of a province and its inhabitants. Generals could then effectively rule these territories on their own without the support of Rome.
This made the Roman provinces increasingly independent and less loyal to the city of Rome. Some of these military generals would even claim themselves emperor, which would almost always lead to civil war.
Rome’s dependence on military might made keeping control over its own provinces just as difficult as protecting its imperial borders.
Loyalty, though, could be bought. Bribes to military generals, either in the form of money or political power, would keep Rome at the center of affairs. But, again, as the empire expanded, this became unsustainable. There were too many people spread across too large of an area to possibly keep everyone happy.
The Death of Alexander Severus
The last Roman emperor to manage to pull this off — keeping everyone happy and the empire at peace, that is — was Alexander Severus, the final emperor of the Severan dynasty. Military victories in Europe and western Asia helped him hold Rome together, but when he died in 235 BC, it was the straw that broke the camel’s back. Whatever had been holding the various regions of the empire together had broken. It plunged into chaos once again.
The Year of Six Emperors
Up until this point in Roman history, we’ve had the Year of Four Emperors (69 AD) and the Year of Five Emperors (139 AD). So, it only makes sense that next would come the Year of Six Emperors.
Jokes aside, that six different claimants emerged after Alexander Severus’ death speaks to how divided the empire had become. These men took their armies up against one another, and within one year, they all were dead.
From this war, however, the Roman empire had been officially split into three parts. The Roman empire itself was just the territory in what is now Italy and north Africa. The Gallic Empire controlled most of what is now Britain, France, Germany, and Spain. And the east, modern-day Turkey, Syria, and Egypt, formed into the Palmyrene Empire.
Powerful provincial leaders and military commanders held such esteem in these provinces they were recognized by the people living there as independent rulers.
For the Romans, this was no good. They weren’t about to surrender a centuries-long empire because it had gotten too big. So, their leader, Aurelian, set out to change it. He defeated the Palmyrene Empire in 273 and the Gallic Empire in 274, a full six years after the Year of Six Emperors.
Aurelian followed up his success with a victorious campaign against the Barbarians in northern Europe, and this helped him solidify his claim to the throne.
An Empire Divided
By 275 AD, Aurelian had died. However, his successor, Diocletian, managed to take his position without too much chaos. But that’s only because he had a plan.
Soon after becoming emperor, using the title augustus, he appointed a second-in-command, a man named Maximian, who would be given the title caesar.
Throughout Roman history, Augustus and Caesar were frequently used as imperial titles. Using them in this sense was a symbol that power would be shared in Rome from that point on.
Diocletian’s next move was to formally split the empire into the Western Roman Empire and the Eastern Roman Empire, appointing Maximian as co-agustus or augusti. Diocletian took the east and Maximian got the west.
This move helped to keep the empire stable, but only for a time. Looking back with the perspective of a historian, this was just one more step along Rome’s decline and eventual fall and division.
The east had become considerably richer and more powerful than the west, despite Rome itself lying in the west.
Going forward, it became the bigger political prize powerful men were willing to fight for. So, while this arrangement from Diocletian ended the Crisis of the Third Century, the Roman empire was far from stabilized. Instead, this Crisis was merely an example of the deep division that existed across the empire and would define its history moving forward.
Written by Matthew Jones