Editing Roman usurper (section)

==Instability==
The first dynasty of the Roman Empire, the [[Julio-Claudian dynasty]] (27 BC – 68 AD), justified the imperial throne with familial ties through [[adoption in Rome|adoption]]. However, conflicts within the family led to the demise of the line. [[Nero]] committed [[suicide]] in 68 as an [[enemy of the people]], resulting in a brief [[Year of the Four Emperors|civil war]]. The [[Flavian dynasty]] started with [[Vespasian]], only to end with the assassination of his second son, [[Domitian]]. Throughout most of the 2nd century, the empire enjoyed relative stability under the rule of the [[Nerva–Antonine dynasty]], but the next century would be characterised by endemic political instability, one of the factors that eventually contributed to the [[fall of the Western Roman Empire]].

[[Commodus]], the last [[Roman emperor|emperor]] of the [[Nerva–Antonine dynasty]], was remembered by contemporaneous chronicles as an unpopular ruler notorious for his extravagance and cruelty, and he was assassinated in 192. As he had no heirs, a struggle for power immediately broke out among the governors of the most important provinces. [[Pertinax]] was elevated to the purple and recognized by his peers, but after 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 he was campaigning in northern [[Roman Britain|Britain]]. The 235 death of [[Severus Alexander]], the last emperor of the [[Severan dynasty]], triggered what historians call the [[Crisis of the Third Century]]. From 235 to the accession of [[Diocletian]] and the establishment of the [[Tetrarchy]] in 286, Rome saw 28 emperors, only two of whom suffered natural deaths (both from the [[bubonic plague|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 since it was a too-common method of acceding the throne. Successful usurpers were usually 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.

The danger of usurpation was greater after the death of an emperor when his successor was not accepted by all provinces. Usually, the legions acclaimed their own commander as emperor on news of the accession of a less popular man. The acclaimed emperor, usually a provincial governor, would then march to Italy or where the opponent was stationed to contest for the purple. However, since legionaries disliked fighting against their brothers in arms, battles between legions rarely transpired. Two main factors decided the success of a usurpation attempt: the loyalty of the legionaries, which were heavily dependent on the amount of booty or monetary prizes promised on victory, and the trust of the military abilities of the commander upon which depended morale. Failure of either part to fulfill one or two of the criteria normally resulted in a mutiny and the death at the hands of their own soldiers. Since the emperors had the ''status quo'' and political credibility behind them, the usurper had to be a charismatic man to avoid doubts in his ranks and an untimely death. [[Emperor Valerian I|Valerian I]], who defeated [[Aemilianus]], himself a usurper, is an example of that kind. Other usurpers, like [[Philip the Arab]], became emperor by a planned murder directed at an established sovereign (in that case, [[Gordian III]]).

However successful, the usurpation procedure always left the new emperor in a somewhat fragile political position since the throne had been attained by violent means. The danger of another usurper was always present, and the first measures taken were inevitably to put trusted men into important commands.{{sfn|Szidat|2010|pp=299-310}} Frequently, the emperor embellished his ancestry and early life to enhance his credibility or the right to the throne. Mentions of obscure [[genealogy|genealogical]] relations with previous popular emperors were common and certainly confused historians. However, most of all, the usurper maneuvered to keep his legions happy since he owed his power to their continued loyalty.