The Plague That Killed Half of Rome

n 165 AD a plague entered Rome and killed up to five million people over fifteen years.

Rome's greatest physician documented every symptom in clinical detail.

Modern science has read those descriptions and cannot agree on what the disease was.

Smallpox. Measles. Something with no surviving equivalent. The data fits all of them. It confirms none of them.

The plague forced Rome to conscript gladiators into its legions. It cracked the empire's defenses. It began the long decline.

And it left no biological trace behind.We will probably never know what it was.