Roman usurper

Usurpers are individuals or groups of individuals who obtain and maintain the power or rights of another by force and without legal authority. Usurpation was endemic during Roman imperial era, especially from the crisis of the third century onwards, when political instability became the rule.

The first dynasty of the Roman Empire, the Julio-Claudians (27 BC – 68 AD), justified the imperial throne by familial ties, namely with the connection (although only through adoption) with Augustus, the first emperor. Eventually conflicts within the Julio-Claudian family triggered a series of murders, which led to the demise of the line. Nero died with public enemy status, and following his suicide a short civil war began, known as the Year of the Four Emperors. The Flavian dynasty started with Vespasian only to end with the assassination of his second son Domitian. The 2nd century was a period of relative peace marked by the rule of the so-called Five Good Emperors, but the next century would be characterized by endemic political instability, one of the factors that eventually contributed to the fall of the Roman Empire in the West.

Commodus, the last emperor of the Antonine dynasty, remembered by contemporaneous chronicles as an unpopular ruler notorious for his extravagance and cruelty, was assassinated in 192. Without sons to be his heir, a struggle for power immediately broke out amongst the governors of the most important provinces. Pertinax was elevated to the purple and recognized by his peers, but following his murder by a restive Praetorian Guard, Septimius Severus decided to make his bid for power and usurped the throne. Although initially a usurper, Severus managed to remain in power for the next 18 years and died a natural death while campaigning in northern Britain. The death of Severus Alexander (the last emperor of the Severan dynasty) in 235 triggered what historians call the crisis of the third century. In this period, from 235 to the accession of Diocletian and the establishment of the Tetrarchy in 286, Rome saw 28 emperors of whom only two had a natural death (from the plague). However, there were also 38 usurpers who raised revolts across the Empire, a clear sign that the security of the frontiers was not the only problem within the Roman world. Usurpation attempts were a constant worry for the emperors in this period; it was a too common method of acceding the throne. Successful usurpers were usually either provincial governors, commanders of a large grouping of Roman legions, or prefects of the Praetorian Guard, which had control of Rome, where the Imperial palace still lay.

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