“If a man were called to fix the period in the history of the world, during which the condition of the human race was most happy and prosperous, he would, without hesitation, name that which elapsed from the death of Domitian to the accession of Commodus.” ~ Edward Gibbon in Decline and Fall of the Roman Empire. Gibbon is talking about the period between 96 and 180 AD: the reign of Nerva, Trajan, Hadrian, Antoninus Pius and Marcus Aurelius. These five rulers are collectively known as “The Five Good Emperors.”
Marcus Aurelius buried the Roman Empire when he made the decision to designate his unwise son Commodus as his successor to the Roman throne. Commodus inherited a reasonably fine empire in 180, but by 192, when he was assassinated in his bathtub, all characteristics of the Roman Empire’s power and culture were tottering, crumbling, and vanishing. When the Roman Empire entered the third century, its political institutions were ossified and its military was demoralized. The barbarians from Eastern Europe to Central Asia realized that the Empire was not capable of defending itself, and they started sacking Roman cities and towns.
The Romans had a premonition that their civilization was coming to an end. They lamented about their fate in letters, plays, poems, and treatises. They blamed the politicians, the military leaders, the barbarians, and the Gods for their travails. What actions did they take to save their civilization? Hardly anything was done to reform the political system, cure the economy, and strengthen the military. Assassinations, coups, civil wars, and massacres became the accepted way of bringing about a change in the government.
The Romans became prone to depression and escapism. Many became addicted to drinking, gambling, and watching gladiator spectacles and chariot races. There was a surge in prostitution. Most prostitutes were slaves, but the Roman citizens were free to engage in the profession of prostitution—and many did, due to economic pressures. Brothels became a popular place of entertainment and relaxation for Roman men. A law passed by Augustus consigned the women accused of adultery to the brothels. Some large brothels were probably state owned.
Mystic cults from Europe, North Africa, and the Middle East flocked to Rome. Many Romans had become convinced that they were powerless to achieve anything, and that the intervention of the supernatural powers was necessary for saving their world. More prayers was their answer to the misery that they saw around them. They became easy prey for the mystic cults.
In the last three centuries of the Roman Empire, the notion gripped the Romans that Italy was the land of weakness and decadence, and that it could not produce a strong Emperor. Political power moved out of Italy, into the provinces of the Empire. Spain, the Balkans, North Africa, and the Middle East (the Eastern Roman Empire) became the new centers of power.
Most Roman Emperors who followed Commodus were born outside Italy. Septimus Severus from Africa, Alexander Severus from Judea, Maximinus the Thracian from Thracia, Philip the Arab from Syria, and several others of non-Roman background became the Emperor one after another. If we define “Romanness” by geography, then it can be argued that even the powerful emperors like Diocletian and Constantine were non-Romans, since they were born in Illyria. In the Eastern Roman Empire, it can be argued that none of the Emperors were of Roman descent.
The toughest legions were stationed in the provinces. They had the power to decide who became the Roman Emperor. They always selected one of their own. In the late third century, an attempt was made under Diocletian and other emperors of a militaristic background to stabilize the political system, fight the barbarians, and safeguard the borders. The army that these military emperors used was partially Roman—it had a large number of barbarian soldiers. The irony was that the Roman emperors were using barbarian soldiers to fight the barbarians. Roman militarism was gone. The Romans did not want to die on the battlefield.
In 378, the Goths proved their superiority over Rome in the Battle of Adrianople by defeating the Roman army and killing the Roman Emperor Flavius Valens. In 410, the King Alaric of the Visigoths sacked Rome. In 455, the Gaiseric and the Vandals sacked the city. In 476, when Odacer, King of Visigoths, deposed the last Roman Emperor Romulus Augustulus and proclaimed himself the King of Italy.