Commodus
Marcus Aurelius Commodus Antoninus (reigned 180-192) is often considered to be one of the worst Roman Emperors, and his reign brought to a close the era of the five good emperors. The son of the popular and successful Marcus Aurelius, his accession to the throne upon the death of his father was at first seen as a hopeful sign by the people of Roman Empire.
However, as generous and magnanimous as his father was, Commodus turned out to be just the opposite. Commodus is often thought to have been insane, and he was certainly given to excess. He began his reign by making an unfavorable peace treaty with the Germanic tribe of the Marcomanni, who had been at war with Marcus Aurelius. Later, Commodus would wage wars of his own against the Germans, often winning partial victories and then claiming honors for them in the Roman Senate.
Commodus also had a passion for gladitoral combat, which he took so far as to take to the arena himself, dressed as a gladiator. This was considered scandalous by the people of Rome, who regarded gladiators as one of the lowest rungs of society. Making matters worse, Commodus' efforts were comical--he entered the arena fully armed and fought hapless opponents armed only with wooden weapons. Dressed as the Greek hero Hercules, Commodus claimed to have slain 12,000 men in gladiatoral combat. For each appearance in the arena, he charged the city of Rome a million sesterces.
Commodus' instability was not limited to this, however. He once had the inhabitants of a city massacred because one of them looked at him with what Commodus thought was an unfriendly glance. He demanded to be worshiped as a god, and he neglected the matters of state while dallying with a harem of some 300 women and young boys. He appointed his cronies to administer the empire, and shared in the money these men stole.
In 190, a part of the city of Rome burned, and Commodus took the opportunity to "re-found" the city of Rome in his own honor, as Colonia Commodiana. The months of the calendar were all renamed in his honor, and the senate was renamed as the Commodian Fortunate Senate. The army became known as the Commodian Army.
A year later, Commodus was strangled in his sleep, a day before he planned to march into the Senate dressed as a gladiator to take office as a consul. Upon his death, the Senate passed damnato memoriae on him and restored the proper name to the city of Rome and its institutions. However, in 195, the emperor Septimius Severus, trying to gain favor with the family of Marcus Aurelius, rehabilitated the memory of Commodus and had the Senate deify him.
The 2000 hit movie Gladiator was loosely based on the career of the emperor Commodus, although it should not be taken as an accurate historical depiction of his life.