Unearthed between 2004 and 2005 in the northern city of York (map), the 80 skeletons were found in burial grounds used by the Romans throughout the second and third centuries A.D. Almost all the bodies are males, and more than half of them had been decapitated, although many were buried with their detached heads.

(Related: "51 Headless Vikings in English Execution Pit Confirmed.")

York—then called Eboracum—was the Roman Empire's northernmost provincial capital during the time.

In a new study of the ancient bones, Gundula Müldner of the University of Reading in the U.K. says the "headless Romans" likely came from