The Roman Empire was well known for its brutality. The reigns of the Emperors were often cut short, whether by war, assassination or unknown illnesses, very few lived to be old enough to die of natural causes or even retire in some rare cases. While the early Roman Empire saw long periods of stability with lasting dynasties there were periods of civil unrest where the mantle of leadership changed frequently. Two notable occasions were the Year of the Four Emperors in 69, and the Year of the Five Emperors in 193. As expected, the reigning Emperors of those years did not last long (save for the final ones of each year).
Eventually the Roman Empire would enter a period known as the Crisis of the Third Century. This era lasted roughly from 235 to 284, from the rule of Barracks-Emperor Maximinus Thrax to Emperor Diocletian, a master politician and administrator who brought the empire back from the brink. This was yet another time marred with short-lived emperors and constant warfare, both from inside and outside of the empire.
Here's a look at the top 10 shortest reigning emperors in the Roman Empire.
10. Herennius Etruscus - 6 months
Herennius Etruscus owes his rise to power to his father, the Emperor Decius. When he was appointed as his father's co-ruler he immediately left Rome to join his father on the northern frontier of the empire to fight the Goths. The two scored a number of decisive victories against their ancient foe.
Cniva, the Gothic ruler was cunning however. He managed to lure Herennius and Decius into a swamp and ambushed them. The fight would be known as the Battle of Abrittus, and was a catastrophic loss for Rome. Both Herennius and his father died in the battle. Herennius had only reigned for 6 short months by this point.
9. Hostilian - 5 months
Hostilian was the son of the Emperor Decius. He remained in Rome living a life of luxury while his father and older brother, Herennius Etruscus, campaigned against the Goths on the northern frontier. When the two died in battle against the Goths, Hostilian was declared Emperor in 251. The legions on the frontier had proclaimed Trebonianus Gallus as the new emperor. Gallus decided to respect Rome's decision and offered to co-rule with Hostilian.
In a rare twist of fate, Hostilian's reign was not cut short by betrayal or war, but instead by disease. In late 251 he contracted the Plague of Cyprian to which he succumbed. His reign lasted roughly 5 months.
8. Pupienus & Balbinus - 3 months, 7 days
Both Pupienus and Balbinus were veteran statesmen in the Roman Empire during the early period of the Crisis of the Third Century. Following the demise of Gordian I and Gordian II in their struggle against Maximinus Thrax, the Senate voted to elect them as the two new emperors in Rome. They had both served as consuls prior to this and so they were the logical choice. To solidify their rule they appointed Gordian III as their caesar, to serve as a prince of Rome.
The two emperors were successful in dispatching Maximinus Thrax, but their attention then turned toward each other. The two became ever suspicious of one another, both believing the other was plotting against them. They split up the Imperial Palace into two halves, neither venturing into the other's section. Eventually they were both killed by their own Praetorian Guard, thus ending their reign of just over 3 months. Gordian III succeeded them as the sole Roman Emperor.
7. Florianus - 3 months
Florianus is yet another victim of the Crisis of the Third Century. Starting his reign in June 276 after succeeding the Emperor Tacticus, who may have been his half-brother. Unfortunately for Florian, mere months into his reign the east rose up against him proclaiming Probus as their emperor.
Despite Florian having a numerical advantage, when the two battled it was Probus who emerged the victor. Florian did not die in the battle but his troops were not keen on a second battle with Probus, and so they mutinied and killed Florian, ending his short reign.
6. Otho - 3 months
Otho was a childhood friend of the Emperor Nero. The two would eventually fall out over a woman, and Otho was sent to an unofficial exile in Lusitania (modern day Portugal). Nero became increasingly unpopular and in 68 Otho joined a rebellion led by Galba against his former friend, thus sparking the Year of the Four Emperors.
Galba became Emperor of Rome in the wake of Nero's death in 69 , but named another as his successor. Otho was infuriated and paid off the Praetorian Guard to murder Galba. The plan worked, and Otho replaced Galba as the new emperor. However, Vitellius, a military commander in Germania marched on Rome to declare himself emperor. The two clashed in a number of skirmishes and battles but Vitellius looked to be the eventual victor. Otho spared the lives of his men by committing suicide.
5. Aemilianus - 2-3 months
The reign of Aemilianus took place right in the middle of the Crisis of the Third Century, so it is no surprise it was a short one. Aemilian was tasked by Emperor Gallus with driving back the Goths who were invading across the Danube in 253. Despite overwhelming odds Aemilian was successful, but his forces despised Gallus who they claimed made too many concessions to the enemies of Rome. In response, they proclaimed Aemilian as emperor.
Aemilian accepted and marched on Rome. Gallus' reinforcements did not arrive in time, and he was abandoned by the senate. Aemilian was hastily accepted as emperor, but Gallus' reinforcements were still on their way to Rome.
Aemilian's forces were tired of war and decided to murder him instead to escape another conflict. The exact dates of his accession and demise are not clear, but he had only ruled between two and three months at the time of his death.
4. Pertinax - 2 months, 27 days
Pertinax was born the son of a former slave. He worked his way up Rome's military, serving in Parthia and Britain and eventually in the Danube region. He was appointed as consul in 192 with Commodus as his co-consul.
Commodus was assassinated at the end of 192 and Pertinax was declared Emperor of Rome by the Praetorian Guard. Pertinax was allegedly an unpopular military commander, once even causing his own soldiers to revolt, and proved to be an equally unpopular emperor too. After trying to instil military doctrine into the Praetorian Guard they assassinated him in the spring of 193, ending his reign after 2 months and 27 days.
3. Didius Julianus - 2 months, 6 days
In third place is Didius Julianus. Julianus was born into a wealthy family and was the descendant of consuls, an office he would later take himself in 175 during the reign of Commodus. Julianus' rise to power was unique, as he was the first person ever to buy his way to the top. When Commodus was deposed in 192 he was quickly replaced by Pertinax who was subsequently murdered by his own Praetorian Guard. The position of Emperor was then auctioned by the Praetorian Guard with Julianus being the highest bidder.
The move proved to be - not surprisingly - unpopular with many. Seeing an opportunity, three generals across the Roman Empire revolted, with Septimius Severus successfully marched on Rome with his legions. Fearing inevitable defeat, a palace guard assassinated Julianus in 193 ending his rule of 66 days. Severus replaced Julianus as emperor, founding the Severan dynasty.
2. Diadumenian - 1 month
Diadumenian comes in second, he was the son of the Emperor Macrinus who swept to power following the death of Caracalla in 217. Diadumenian was appointed as his father's co-ruler in May of 218, aged only 9.
His father Macrinus became increasingly unpopular and eventually the eastern part of the empire revolted against him, instead favouring Elagabalus – a relative of Caracalla. The forces of Macrinus and Elagabalus came to blows at Antioch in 218, with the rebels securing victory. Diadumenian fled with an entourage but was later captured an executed. His reign lasted only one month. His father would be captured shortly after and met the same fate.
1. Gordian I & Gordian II - 21 days
In at number one are the father and son duo, Emperor Gordian I and his son, Gordian II. They reigned at the start of the Crisis of the Third Century. Initially Gordian I had been tasked with putting down rebellions across North Africa which had come about as a result of increased taxation by the Emperor Maximinus Thrax. Gordian I was persuaded to join the rebel cause and declare himself emperor, which he did on the condition that his son would join him. In 238 they officially declared themselves joint emperors of Rome – a move quickly ratified by the Senate who despised Maximinus Thrax.
Their reign was cut very short however, when the governor of neighbouring Numidia launched an attack on Carthage, killing Gordian II in battle and causing Gordian I to later commit suicide. They ruled for only 21 days which makes them the shortest reigning emperors ever.