In 193 AD, after the assassination of Emperor Commodus, the Roman Senate arose under the guidance of Publius Helvius Pertinax to reinstate the principles of republicanism after more than two centuries of rule by emperors.

Rome Returns to the RepublicCommodus was the son of Marcus Aurelius, a good emperor who ruled for some twenty years. Aurelius had been more of a philosopher king than a politician, writing his Meditations on self-guidance in Greek, possibly in imitation of the ancient wise men of Greece. He took his rule as a civic duty, establishing justice and fighting numerous wars for the good of Rome even though he preferred study. Aurelius died in Vindobona (modern Vienna) while on campaign in 180, succeeded by his son, Commodus.

A new story by Jeff ProvineCommodus had already ruled as co-emperor for three years and, though young, assumed full command with all skills needed, but his father had not anticipated him squandering them. Dio Cassius, a contemporary historian, recorded that Commodus began to turn Rome "from a kingdom of gold to one of rust and iron". Commodus ignored the business affairs of state and instead took to entertaining the army and populace with enormous monetary gifts and lavish games. Most notoriously, Commodus would reject tradition and participate in the gladiatorial combat himself. Early in his reign and then throughout, dissatisfied leaders would organize conspiracies against him, finally culminating in his death at the hand of his mistress Marcia, his manager Eclectus, and the Praetorian Prefect Quintus Aemilius Laetus December 31, 192.

Pertinax, the praefectus urbi (roughly, Mayor of Rome), was taken by the Praetorian Guard and prepared to be named emperor, even against his will. After a night of expert reasoning and discussion, Pertinax finally managed to persuade the Praetorian soldiers to end the tradition of obeying an emperor and instead uphold their oath to the Senatus Populusque Romanus (the Senate and People of Rome). Marching into Rome in celebration, the Senate was convened and ancient legal books brought out of libraries to bring back the great Republic that had been dissolved into August's empire when Rome was so corrupt. Corruption had now swallowed up the office of imperator, and it was time for the Republic to stand again.

Great new powers were granted to the prefects in the provinces around the empire and citizens were enabled to vote for representation among the censors. The Senate took up many pet projects that had gone undone while the bureaucracy ruled, and Pertinax himself retained his position as praefectus urbi, spending much of his tenure restoring solvency and maintaining the grain supply to Rome. The Praetorians were broken up diplomatically, paying commanders enormous sums to retire or head eastward in General Septimus Severus's campaign to conquer Mesopotamia while soldiers were dispersed through the legions protecting the empire at large. Without the Praetorian Guard taking great bribes and influencing politics with the sword, Rome transitioned fairly peacefully into the New Republican Era.

In 251, the Plague of Cyprian spread through the empire. In Rome, it was rumored that some 5,000 people died each day. The Senate proved powerless to stop the suffering, several potential solutions being frozen in debate while disease raged. Prefects maintained control by establishing quarantine zones, cutting off their borders and taking executive powers. By the time the plague itself finished, the provinces were sick of making payments to an ineffective Rome that now could scarcely defend its own borders. The empire collapsed as Parthia rebelled and no one stopped them, followed by Egypt, Asia Minor, and spreading westward until Rome had become a checkerboard of mismatched kingdoms, republics, and city-states by the beginning of the fourth century.

Germanic invasions soon followed, turning the Mediterranean into a series of feudal states built upon self-defense. Trade dwindled, and a dark age settled across Europe and northern Africa. In the East, the Persian Empire arose, dominating much of the Levant and maintaining trade along the Silk Road, growing wealthy as it fed luxuries to the west, such as the Hun Empire, Kingdom of the Franks, and New Carthage.