Pertinax (126-193 CE) was born the son of a freed slave, and worked as a teacher before becoming an officer in the army. Successful campaigns against the Parthians saw him rise in rank and prestige, with Pertinax eventually rising to become a member of the Senate.

Pertinax was declared emperor by the Praetorian Guard after the death of Commodus, where he immediately tried to institute several sweeping reforms. One of these reforms was the restoration of discipline amongst the pampered Praetorian Guard, making enemies that ultimately resulted in Pertinax's assassination by members of the Guard just under three months into his reign. After his death, the Praetorians acutioned off the imperial title, resulting in a brief civil war and the year 193 CE becoming known as the Year of the Five Emperors.

Pertinax was later deified by Septimius Severus, the emperor after Pertinax's successor, Didius Julianus. His reputation throughout history has largely been a positive one, though his short reign has made it difficult to dertermine what his rule would have truly been like.