Antonine Plague
The Antonine epidemic emerges in the East and reaches Rome
View full image ↗ How was this image made?
The creative brief sent to the image model. These are instructions, not a record of what actually happened.
Original prompt & settings (JSON) ↗Galen was in Rome when the epidemic arrived in 166 — and left the city soon afterward.
Mesopotamia to Rome in under a year
A severe epidemic emerged in Mesopotamia in late 165 or early 166, during Lucius Verus's Roman campaign against the Parthian Empire.
It reached Rome in 166, less than a year after the eastern outbreak. Galen was in the city when it arrived, and he left soon afterwards.
The returning-army story
The traditional account links the disease's westward movement to soldiers coming home from the Parthian war. Recent scholarship cautions that this story may partly reflect imperial propaganda.
Galen met the epidemic again among troops at Aquileia in the winter of 168–169, recalling that both emperors fled toward Rome while much of the army stayed behind.
"Plague" here does not mean plague
The word denotes a destructive epidemic. It does not establish infection by Yersinia pestis, and this outbreak is not the Plague of Justinian, which began roughly 375 years later.
Galen's symptom descriptions suggest smallpox strongly to some medical historians, but no ancient DNA has identified the pathogen, and the National Library of Medicine describes the evidence as equivocal. The epidemic is securely attested at least until 180, possibly into Commodus's reign.
Sources
Researched 23 Aug 2026 6 sources not yet audited Date disputed
How this was checked
Researched from the web into a fact sheet and rewritten from that sheet. This article has not yet had an independent model audit. How the pipeline works →
Date disputed. Sources disagree; the research places it at ~0166.
What the sources leave uncertain
- The onset is variously placed in late 165 or early 166; 166 is secure as the year the epidemic reached Rome, not necessarily the year it began.
- Galen's symptoms strongly suggest smallpox to some medical historians, but no ancient DNA has identified the pathogen and the National Library of Medicine describes the evidence as equivocal.
- The term plague here means a destructive epidemic; it does not establish infection by Yersinia pestis.
- The returning-army narrative is plausible but not securely proven.