We cannot know the actual mortality rate with any certainty, although there is no doubt that it was high. Seeck’s estimate, made in 1910, that over half the population of the Empire perished, now seems too high (in Littman and Littman). Conversely, Gilliam’s conclusion that only 1 percent died is incompatible even with his own assertion that “a great and destructive epidemic took place under Marcus Aurelius.” The Littmans propose a rate of seven to ten percent, but do so by selecting smallpox epidemics