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Caligula - His blood-soaked reign only lasted four years, but even 2000 years after his assassination his name is synonymous with some of the basest forms of cruelty, sadism, and madness.

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Caligula - To be fair to the man, he didn't exactly have it easy growing up. He was the only male survivor of a bitter succession feud and saw his entire family massacred before ascending to the throne.

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Caligula - The most famous story about him is that he named his favorite horse, Incitatus, consul. However, this is generally accepted as not true.

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Caligula - Few records survive of his reign, but it is widely believed to be among the bloodiest of the empire.

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Commodus - Commodus, played by Joaquin Phoenix in 2000's completely fictionalized 'Gladiator,' was the first emperor after a period we now refer to as the Age of the Five Good Emperors.

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Commodus - He loved gladiatorial combat and fought in arenas—and he always won! Which surely was solely due to his having honed his skills during years of practice, and had nothing at all to do with the fact that he was, you know, emperor...

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Commodus - Loved by the common people but despised by the upper classes, he spent like there was no tomorrow on games and his own cult of personality, leaving the empire in financial tatters for years to come. Still, he seems to have had fun doing it.

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Caracalla -

Though their father, Emperor Septimus Severus, wanted Caracalla to run the empire together with his brother after his death, they hated each other's guts. So he did what any rational human being would do: he lured his brother into a trap and killed him in front of their mother's eyes.

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Caracalla - His cruelty didn't stop there, however. His father's dying advice to him was: "Enrich the soldiers, and scorn all other men." Which is pretty much what he did.

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Caracalla - Caracalla's reign does actually mark the end of slavery in the Roman Empire. But this was not for any humanitarian reason. He needed more citizens to tax to keep the soldiers in the lifestyle they'd become so accustomed to, and to thus prevent a military coup.

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Nero - Only 17 when he became emperor, Nero will rightfully, or wrongfully, always be known as the man who played the fiddle while his city burned during the Great Fire of Rome. Nero to this day is associated with fire.

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Nero - Some biblical scholars even believe the number 666 in the Book of Revelations to be a direct reference to him. What's more, he was the first Roman emperor to persecute Christians in earnest, blaming them for the infamous fire.

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Nero - Oh yeah, he also poisoned his mother, murdered his pregnant wife, and afterwards saw a boy who looked just like her, forced the boy to marry him, dress as a woman, and be castrated. Kind of puts that whole fire thing into perspective, doesn't it?

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Septimius Severus -

As you probably gleaned from his dying words of advice to his son and successor Caracalla ("Enrich the soldiers, and scorn all other men"), Septimus Severus was a military man.

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Septimius Severus - And he was a real stickler for the rules. He, unsurprisingly, managed to unify the army, but was without mercy for anyone that didn't adhere to Roman religious practices.

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Septimius Severus - Which in the real world meant the ruthless persecution of Jews and Christians throughout the empire under his reign.

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Tiberius -

Tiberius was only the second emperor, and he actually was a reluctant one. Some of the cruelest excesses of imperial rule pretty much started with this guy.

Politically he is mostly known for show trials and purges, which somewhat strangely were probably quite instrumental in solidifying the empire.

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Tiberius - Not long after becoming emperor he basically withdrew into his villa outside of Rome and led a life of such debauched depravity that in today's world it would easily see him imprisoned for life.

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Augustus - The first, the greatest, and the longest-reigning emperor is rightfully lauded as being the architect of the empire as it switched from being a republic.

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Augustus - However, he wasn't without his bizarre excesses either. He was known for a bunch of bizarre morality laws. For instance, young widows who didn't remarry would not be allowed inheritance.

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Augustus - He even went so far as to banish his own daughter for 'frolicking.' Married (forcibly) three times, she was known to have extramarital affairs. Clearly not the kind of PR you need when in the midst of constructing an empire.

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Elagabalus - Elagabalus died at 18, having been emperor for four years. In his short life, he was married five times, tried to replace Roman religion with his own, and spent enormous sums of money on building temples.

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Elagabalus - Unsurprisingly, the Romans didn't take kindly to this and had him assassinated.

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Julian the Apostate - Julian the Apostate actually seems to be one of the good guys on this list, if not extremely misguided. He was Roman emperor almost 30 years after the death of Constantine the Great, the man who had christened the empire.

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Julian the Apostate - Despite the fact that early Christian scholars depicted him as just as cruel of a persecutor of Christians as some of his predecessors, his private writings actually reveal a very tolerant attitude toward them.

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Julian the Apostate - He would be the last non-Christian ruler of the Roman Empire. The man stuck to his guns, you have to respect that. Still, it was never meant to be and he died on the battlefield two years into his reign.

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Domitian - Domitian was the emperor who preceded the Age of the Five Good Emperors, probably the most peaceful and prosperous time of the empire.

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Domitian - But first there was the almost two-decade reign of one of the most paranoid and spendthrifty emperors up until that time.

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Domitian -

Domitian was also known as a rabid anti-Semite and an enthusiastic persecutor of Jews and Christians.

See also: Discover amazing Roman sites and ruins from across the Empire.

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