Wherever there is an out-of-the-way war, there will be mercenaries — hired fighters whose only common bond may be a hunger for adventure. Some join foreign armies or rebel forces because they believe in the cause; others sign on because the price is right.

This was true in ancient Greece, although you wouldn’t know it from ancient Greek historians, for whom the polis, or independent Greek city-state, symbolized the demise of kingly oppression and the rise of citizen equality and civic pride. For instance, neither Herodotus nor Diodorus Siculus mentioned mercenaries in their reports of the first Battle of Himera, a fierce struggle in 480 B.C. in which the Greeks from various Sicilian cities united to beat back a Carthaginian invasion. Mercenaries were considered the anтιтhesis of the Homeric hero.

“Being a wage earner had some negative connotations — avarice, corruption, shifting allegiance, the downfall of civilized society,” said Laurie Reitsema, an anthropologist at the University of Georgia. “In this light, it is unsurprising if ancient authors would choose to embellish the Greeks for Greeks aspect of the battles, rather than admitting they had to pay for it.”

But research published on Monday in the Proceedings of the National Academy of Sciences suggests that the ancestry of the troops defending Himera was not as strictly Greek as historical accounts of the time would have it.

The victory was widely seen as a defining event for Greek idenтιтy. But the new study, an analysis of degraded DNA from 54 corpses found in Himera’s recently unearthed west necropolis, found that the communal graves were largely occupied by professional soldiers from places as far-flung as those known today as Ukraine, Latvia and Bulgaria.

The finding ʙuттresses research published last year in which Katherine Reinberger, a bioarchaeologist at the University of Georgia, and her colleagues performed a chemical analysis of the tooth enamel of 62 fallen fighters buried near Himera’s ancient battlefield, where two major clashes played out: one in 480 B.C., when Himeran forces defeated the Carthaginian general Hamilcar Mago, and a second battle seven decades later, when Hamilcar’s grandson returned for revenge and Himera was destroyed. Dr. Reinberger’s team concluded that about one-third of those who fought in the first conflict were locals, compared with three-fourths in the later battle. Dr. Reitsema is a principal author on both studies.

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