I am looking for approximate number of people that died in Europe during 541–542 Plague of Justinian.

All wiki has is

Modern scholars believe that the plague killed up to 5,000 people per day in Constantinople at the peak of the pandemic


Frequent subsequent waves of the plague continued to strike throughout the 6th, 7th and 8th centuries, with the disease becoming more localized and less virulent. One high estimate is that the Plague of Justinian killed as many as 25 million people across the world

If I would say that it killed 5 mil how wrong would I be?

  • It is impossible to know such things. Any "estimates" you may find of plague deaths, especially at so early a period are generally complete guesses. Dec 8, 2014 at 18:54

1 Answer 1


As Mr. Durden says, any estimate is going to have a very wide range/confidence interval. If you want an answer to the question you asked, you're probably better off asking in a math stack exchange about statistics.

Having said that, 10 minutes of research will answer your question. Starting with the page you cite and checking the references, the List of Epidemics, we see that the Plague of Justinian is estimated to have killed 40% of the population. Medieval demography tells us that during late antiquity the population fell from 70 million to 50 million and reached a minimum in response to the Plague of Justinian and the extreme weather events.

70* 0.4 is 28

if you want a low confidence estimate, then you could say that the true number is probably between 28 million and 20 million. (28 million based on the 40% estimate, 20 million based on the population minimum listed in medieval demography).

If you want a higher confidence estimate, you'd need to do more research. But as Mr. Durden says, you're never going to reach a high confidence estimate.

  • 1
    Are you sure that wasn't just meant to be 40% of the population of Constantinople? Infectious diseases tend to hit cities the hardest.
    – T.E.D.
    Dec 8, 2014 at 19:18
  • 1
    40% LOL. The most deadly epidemic in the US was the Spanish influenza killing an estimated 675,000 people, less than 1% of the population. My experience with plagues is that people make all kinds of wild exaggerations. When you have actual REAL numbers they never bear out such exaggerations. Just general principles of epidemiology alone makes any death rate over 15% very unlikely, even for the most virulent disease possible. The only places you will find higher rates is when the population is forcibly confined in close quarters, like in a prison. Dec 8, 2014 at 20:04
  • 5
    @TylerDurden Actually the black death killed between 30 and 60 % of the European population. en.wikipedia.org/wiki/Black_Death
    – Jeroen K
    Dec 9, 2014 at 8:47
  • 3
    As I understanding it, survival rates are correlated with nutrition & general health, and the current hypothesis is that everyone who survives today inherited a partial immunity to 'Y Pestis'; those without the immunity have no descendants. That said, your point stands; our estimates of mortality rates must have a wide variation, because our confidence in the records is low.
    – MCW
    Dec 9, 2014 at 15:32
  • 1
    @TylerDurden But modern people don't believe washing is how you get the plague. Also there are a lot of sources talking about the death tolls in cities. This is the fourteenth century, not only the clergy could write. These cities had lists of their citizens btw, the numbers where not just wild guesses.
    – Jeroen K
    Dec 20, 2014 at 10:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.