Overview
The Plague of Cyprian was a pandemic that afflicted the Roman Empire from about AD 249 to 262, or 251/2 to 270. The plague is thought to have caused widespread manpower shortages for food production and the Roman army, severely weakening the empire during the Crisis of the Third Century. Its modern name commemorates St. Cyprian, bishop of Carthage, an early Christian writer who witnessed and described the plague. The agent of the plague is highly speculative because of sparse sourcing, but suspects have included smallpox, measles, and viral haemorrhagic fever (filoviruses) like the Ebola virus.
Contemporary accounts
There are no accounts comprehensive enough to estimate the total number of deaths of the plague in the Roman Empire. At the height of the outbreak, 5,000 people a day were said to be dying in Rome. One historian has calculated that the population of Alexandria dropped from 500,000 to 190,000 during the plague. Some of the decline in the city's population was probably due to people fleeing. Pope Dionysus the Great wrote about the plague's effects in Alexandria soon after the Decian persecution of 250 or Valerian persecutions of 257, as reported by Eusebius:
Cyprian's biographer, Pontius of Carthage, wrote of the plague at Carthage:
Afterwards there broke out a dreadful plague, and excessive destruction of a hateful disease invaded every house in succession of the trembling populace, carrying off day by day with abrupt attack numberless people, every one from his own house. All were shuddering, fleeing, shunning the contagion, impiously exposing their own friends, as if with the exclusion of the person who was sure to die of the plague, one could exclude death itself also. There lay about the meanwhile, over the whole city, no longer bodies, but the carcasses of many, and, by the contemplation of a lot which in their turn would be theirs, demanded the pity of the passers-by for themselves. No one regarded anything besides his cruel gains. No one trembled at the remembrance of a similar event. No one did to another what he himself wished to experience.
In Carthage, the Decian persecution, unleashed at the onset of the plague, perhaps inadvertently led to the criminalization of Christians' refusal to take an oath. Fifty years later, a North African convert to Christianity, Arnobius, defended his new religion from pagan allegations:
From Wikipedia (CC BY-SA 4.0).