From the Harvard Crimson:
"The new paper, “The diverse genetic origins of a Classical period Greek army,” published in Proceedings of the National Academy of Sciences, takes a genomic look at those foreign fighters. A previous study used isotopes to identify three-quarters of those in the mass graves as “non-local.” Now, the archaeologists from that study — including Professor of Genetics and Human Evolutionary Biology David Reich, co-first authors Laurie Rietsema (University of Georgia) and Britney Kyle (University of Northern Colorado), were able to carry out an in-depth dive into genome-wide data from 16 individuals from these mass graves (as well as 38 other ancient people from Sicily). Their analysis revealed that individuals from the mass graves, assumed to be largely mercenaries, hailed from places as far-flung as Ukraine, the Baltic region (modern-day Latvia), and Thrace (modern-day Bulgaria), said Reich.
Going into the study, “We already had an idea that people from lots of regions must have participated in this battle, but there was no clue yet as to where they came from,” said Alissa Mittnik, the postdoc in Reich’s lab who led the genetic analysis and another co-first author."
Read more here.