Ironically, Marius's reforms had made the legions fiercely loyal to their individual generals rather than the state, which allowed Sulla to march his army against Rome and force Marius into exile. With that, Rome's first civil war was officially underway.

Even in his time, Caesar was in many ways larger than life, and because of his legacy as virtual founder of the Roman Empire, much of what was written about - and by - him during his life and immediately after his assassination was politically motivated. The fact that he was murdered on the Ides of March is universal knowledge, but it's often forgotten that he was stabbed while entering the Curia of Pompey, one of the Senate's meeting places, in March of 44 B.C. The curia was a theater dedicated to Pompey the Great, Caesar's rival in the civil war that ended the Republic and made Caesar dictator. When Caesar was stabbed, he fell at the base of a colossal statue of Pompey. Thanks to Caesar's victory in the civil war, Pompey is mostly remembered not for being one of Rome's greatest generals, but for being defeated by Caesar and then ignominiously murdered after he fled to Egypt, where the boy pharaoh Ptolemy XIII decapitated Pompey and offered his head to Caesar as a gift.

The 50 years following the assassination of Severus Alexander on March 19, 235 A.D. has been generally regarded by academics as one of the lowest points in the history of the Roman Empire. This stands in stark contrast to the previous 150 years, which included the reigns of the Five Good Emperors and has been universally praised as one of the high points of the empire. Severus Alexander was the last of the Severan emperors, and the subsequent years of crisis were characterized by a series of short reigns, usually ending in the violent death of the reigning emperor.

At the same time, this period of time also saw the empire beset by threatening forces on all sides. The Romans faced a newly resurgent Persia in the east, as well as significant forces from German tribes on the Rhine and Goths along the Danube. The various conflicts would result in the unprecedented death of a sitting emperor in battle, which took place in 251 with Emperor Decius, and Emperor Valerian was captured in 260 A.D. As Roman leaders vied with each other for power and constantly fought civil wars, Rome's famous roads fall into disrepair, the economy was crippled, the continent-wide trade system that had flourished in the previous years was replaced with a basic barter system, and there was a reduction in international trade.