Antonine Plague

The Antonine Plague of 165–180 AD, also known as the Plague of Galen (from the name of the Greek physician living in the Roman Empire who described it), was an ancient pandemic brought back to the Roman Empire by troops returning from campaigns in the Near East. Scholars have suspected it to have been either smallpox or measles, but the true cause remains undetermined. The epidemic may have claimed the life of a Roman emperor, Lucius Verus, who died in 169 and was the co-regent of Marcus Aurelius Antoninus, whose family name, Antoninus, has become associated with the epidemic. The disease broke out again nine years later, according to the Roman historian Dio Cassius (155–235), causing up to 2,000 deaths a day in Rome, one quarter of those who were affected, giving the disease a mortality rate of about 25%. The total deaths have been estimated at five million, and the disease killed as much as one-third of the population in some areas and devastated the Roman army.

Ancient sources agree that the epidemic appeared first during the Roman siege of Seleucia in the winter of 165–166.Ammianus Marcellinus reports that the plague spread to Gaul and to the legions along the Rhine. Eutropius asserts that a large population died throughout the Empire.

Rafe de Crespigny speculates that the plague may have also broken out in Eastern Han China before 166, given notices of plagues in Chinese records. The plague had an impact on Roman culture and literature, and may have severely affected Indo-Roman trade relations in the Indian Ocean.

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