Septimius Severus (145-211 CE) was born in the Roman province of Africa; and advanced steadily through the customary succession of offices (the 'cursus honorum') during the reigns of Marcus Aurelius and Commodus. He was governor of Pannonia Superior when word of Pertniax's murder and Didius Julianus' accession reached him in 193 CE.

In response to Julianus' controversial accession through buying the emperorship in an auction; many rivals rose up and declared themselves emperor; with Severus being one of them; beginning what was known as the Year of the Five Emperors. Hurrying to Rome; Severus executed Julianus; and then fought his rival claimants for control of the Empire. By 197 CE; he was the sole power in the Empire; and began once more waging war to expand the borders of the Empire.

Severus fell ill in late 210 CE; fatally so; and died in early 211 CE. He was succeeded by his sons Caracalla and Geta; founding the Severan dynasty; the last dynasty of the Roman Empire before the Crisis of the Third Century.