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How Emperor Aurelian Reunited the Roman Empire

The Roman Empire when Aurelian took the throne in 270 AD.

The Roman Empire when Aurelian took the throne in 270 AD.

The mighty Roman Empire ruled the Mediterranean world for centuries after the conquests of the Republic were consolidated under the rule of the first emperors of the Eternal City. Although the expansion of Rome eventually came to an end, the empire was still stretching from the Sahara to the wall of Hadrian, from the Pillars of Hercules to the Euphrates. Historians believe that the empire reached its zenith during the late 1st and early 2nd century AD, and this period was the apogee, the peak of the Roman Empire.

However, like every other golden age of history, the golden age of the Roman Empire came to an eventual end. Contemporaries like Cassius Dio were already commenting that their age at the beginning of the 3rd century AD was an age of iron and rust, and only a pale shadow of the golden age of Marcus Aurelius. Some historians consider that the decline of the empire began with the reign of Commodus, and from that time on, it was a slippery slope towards the end.

Whatever the truth, it is true that the 3rd century put an end to the Pax Romana, the peaceful centuries that the citizens of Rome enjoyed after Emperor Augustus took power and defeated his internal enemies, which brought an end to the devastating civil wars that plagued the last decades of the Republic.

The Third Century Crisis

After the last member of the Severan dynasty, Alexander Severus, was murdered in 235 AD, began a period which became known as the 3rd Century Crisis. A period of fifty years during which time civil war, foreign invasion and economical crisis threw the empire in disarray and very nearly lead to the complete and utter collapse of the Roman Empire.

In the period between 235 and 284, more than thirty emperors followed each other, with most of them falling victims of assassinations.

After a terrible defeat suffered by Emperor Valerian at the hands of the Sassanid Empire at the Battle of Edessa, the Roman East was overrun by the forces of Shah Shapur. With the emperor captured and the Roman field army wiped out, it was not the Romans who defended the East, but a Romanised Arab warlord named Odaenathus, the ruler of Palmyra.

Between 260 and 267, Odaenathus was the de facto ruler of the East, and it was him, and not Emperor Gallienus, who fought and defeated Shapur. Odaenathus was assassinated in 267 and was succeeded by his young son, but it was his queen Zenobia who was the real ruler of the Palmyrene Empire.

The commanders of the Gallic and Brittanic legions also decided to sever their ties with Rome in the aftermath of the defeat of Valerian and created the independent Gallic Empire.

The rest of the empire was kept together by the son of Valerian, Gallienus. He made several reforms in the empire, most importantly in the army, where he largely sidelined the amateur aristocratic officers and heavily favoured the equestrian class. Gallienus defended the empire from usurpers and barbarian incursions, but he fell victim to a conspiracy in 268 AD when he was murdered by his own high ranking officers.

The Rise of Aurelian

Gallienus was succeeded by one of his commanders Claudius, who promoted Aurelian and the latter became his right-hand man and chief cavalry commander.

The Romans were busy fighting the next two years against Germanic invaders around the Alps and in the Balkans. Emperor Claudius fell ill in 270 AD and relinquished command to Aurelian, who largely defeated the Goths who invaded the Balkans. Aurelian soon received news that Claudius died of the plague.

What followed the death of Claudius was very typical of the 3rd century. The Senate supported the younger brother of Claudius, Quintillius, to become the new emperor of Rome, while the main Roman army that was campaigning in the Balkans chose to ignore the Senate and elected Aurelian, who was the most respected and capable of their commanders as the new Roman emperor.

Aurelian and Qunitillius clashed, and Aurelian emerged as the victor, while his rival died during or in the aftermath of the battle.

After he secured his throne from Quintillius, Aurelian had to march against an army of Germanic invaders who were ravaging Northern Italy. The Emperor was careless in the initial phase of his campaign, and his army was ambushed by the invaders near Placentia. Still, the Roman army was not wiped out, and Aurelian rallied his troops and expelled the invaders after the initial setback.

There were some visible changes that were clear to see for everyone, however, as the towns and the cities of the empire became more and more vulnerable, began a program of fortifying these settlements with walls, the most well-known example was the famous Aurelian Walls around Rome itself.

Aurelian tried to cut back on the corruption that plagued Rome and even attempted to reform the coinage system. However, it is telling enough just how much value Roman coins lost by the time of Aurelian that his new improved coins had a silver purity of 5%, while the coins of Marcus Aurelius, a mere 100 years before, had a silver purity of over 80%.

Aurelian was faced with opposition in Rome, and as his enemies incited riots against him. The Emperor had to resort to brute force to crush his enemies, which cost several thousand if not more citizens their lives.

Once Aurelian was finished in Rome, he had to depart for the Balkans, which were once again ravaged by Gothic raiders. The Romans pushed back the Goths over the Danube. Aurelian lead a punishing attack over the Danube also and defeated the Goths, but the Emperor also realised that the Roman Province of Dacia was indefensible in the current circumstances and ordered the Roman soldiers, officials and citizens to evacuate Dacia and relocate south of the Danube.

The land of the evacuated province was given to Roman friendly Germanic and Sarmatian tribes, who were to serve as a buffer between the empire and the people beyond the frontiers.

Reunification of the Empire

In the aftermath of his victories in 271, the emperor made preparations for the next year's campaign against the Palmyrene Empire. He gathered a large army, most probably well over 50,000 men, which included some of the most experienced legions which have fought in the Balkans in previous decades.

The Emperor crossed into Asia Minor in early 272, and his march was unopposed until he reached the town of Tyana in Eastern Anatolia. Aurelian had a volcanic temperament, and upon receiving the defiant message of the town, he flew into a rage and threatened to not leave a dog alive in the town once his soldiers breached the walls. With time the Emperor’s temper calmed, and when the town fell after a short siege, he ordered his men to spare the city, much to the dismay of the soldiers who were rather looking forward to looting the town.

The clemency of the Emperor helped him greatly in the aftermath of the campaign, as more and more towns decided to surrender after they heard how lenient Aurelian was with Tyana.

The Palmyrene general Zabdas faced Aurelian near Antioch, but his cavalry was defeated by the Romans.

The two armies met again at the Battle of Emessa not much later, and once again, the Romans emerged victorious. Their victory allowed them to march directly on Palmyra and besieged the capital of the Palmyrene Empire. Queen Zenobia was captured while she tried to escape in disguise, and not much later the city of Palmyra surrendered to the Romans.

Map of the Roman Emperor Aurelian's march to Palmyra AD 272.

Map of the Roman Emperor Aurelian's march to Palmyra AD 272.

Queen Zenobia was spared by the Emperor, but he paraded his enemy through the streets of the towns he passed. With his mission accomplished in the east(as a lieutenant of the emperor retook Egypt while the main Roman army was fighting in Syria), he turned west and by 273 AD, Aurelian was back in the Balkans, fighting against yet more invaders and raiders.

News that the leaders of Palmyra were planning a rebellion forced the Emperor to turn East again and he captured the city. This time he was not lenient, and although he allowed the citizens to leave, Palmyra was destroyed, and it never quite recovered from it. With a rebellion going on in Egypt, the Romans marched south and quashed the revolt in 273 before setting sail for Rome.

With Egypt and Palmyra back under Roman control, Aurelian only had to defeat the Gallic Empire to finally reunite the Roman Empire. Preparations were made, and by the spring of 274, the invasion was underway.

The armies met near Chalons, and in either a battle, surrender or a combination of both, Aurelian defeated the forces of the Gallic Empire. The details about the battle are murky, and some ancient historians doubt whether there was a real battle at all, and if there was, whether Tetricus abandoned his army or was captured during or in the aftermath of the battle.

What is the exact truth probably will never be known, but what is for certain is that Aurelian emerged victoriously and reunited the Empire. Tetricus was spared, and although he had to suffer the indignity of being paraded through the streets of Rome in the parade of Aurelian, later he received a position in the imperial administration and lived out his days peacefully.

Death of Aurelian

Aurelian held his triumph in the aftermath of his victories. The next year he was on campaign again and was leading his armies in the Balkans. Aurelian was a very strict man and punished harshly his officials and soldiers who were involved in corruption.

One of his secretaries lied to the Emperor about a minor matter and feared what would happen to him once the lie was uncovered. He, therefore, forged a letter which contained a list of names of the officers of the army who were about to be put to death. The terrified soldiers decided to act first and murdered Aurelian in September 275.

However, the secretary did not escape his punishment. The soldiers soon found out about the deceit and were overcome with grief and outrage, which they unleashed upon the man who tricked them into killing their Emperor.


Heather, Peter. (2005). The Fall of the Roman Empire: A New History of Rome and the Barbarians. Oxford UP.

Goldsworthy, Adrian. (2010). How Rome Fell: Death of a Superpower. Yale UP.

Southern, Pat. (2001). The Roman Empire from Severus to Constantine. Routledge.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2022 Andrew Szekler