The first four of the wise men of Rome, had no natural children to succeed them. In adopting an heir, they established that person's right to rule and thereby avoided the sub-plots and infighting that followed the death of an Emperor. The last of the five Emperors, Marcus Aurelius, perhaps the most popular of all, had a natural son, who was by some convoluted family ties, related to the previous Emperors as well. He co-reigned for three years before his father died, and it was thought that all would be well. Not.

Today, Commodus is considered one of the worst Roman rulers, on a par with Nero and Caligula. Many historical accounts state that he was insane, or suffering from at least some kind of personality disorder. The excesses of his nearly eleven years in office, are the stuff of legends.

Commodus would wage campaigns and scrape out a half-hearted victory, but claim full honors when he returned home. All over Rome, he had his statues dressed in the lion's hide as Hercules had been, and then sought to emulate the great hero by fighting wild animals in the arena. When that did not satisfy him, he moved on to gladiator fighting, which horrified the citizenry, who saw gladiators as just about the lowest strata of society.

By 190A.D. when part of Rome burned, Commodus was so wrapped up in himself, that he felt in rebuilding the city he was re-creating it in his own image, and had it officially renamed Colonia Commodiana. That was such a good idea, he went on to rename all the months of the calendar after himself, re-styled the Senate as the Commodium Fortunate Senate, and the troops became Rome's Commodian Army.

Little wonder someone strangled him in his sleep, less than a year later.