Some 3,200 years ago—about 100 years before the fabled sacking of Troy—an epic Bronze Age battle for a bridge in what is now a marshy area of northern Germany was fought.

Looking for all the world like extras in Lord of the Rings, thousands of soldiers clad in skins, protected by shields, and attacking with clubs, swords, and bows and arrows converged. Men and battle horses alike died in an apocalyptic fight.

Despite its scale and brutality, the battle was eventually lost to history. (Writing wouldn’t become common in that part of the world for another 2,000 years.) But in 1996 an amateur archeologist found, sticking out of a riverbank, an arm pierced by an arrowhead. Soon after, the first few crumpled bodies and skulls were found.

In 2009 and 2015 careful excavations of only about 1/10^th of the dig unearthed about 10,000 bones. A geomagnetic survey in 2013 found evidence of a 120-yard-long bridge. And this August journalist Andrew Curry describes in Science the archeologists’ emerging picture of the earliest known episodes of large-scale violence in European history and of an approach to war that seems to have gone way beyond local clan fighting local clan.

The soldiers in this battle used weaponry that was both standardized and uncommonly heavy, suggesting that mobilizing and training the men was itself an enterprise. DNA from the soldiers’ teeth point to ancestries that varied widely.

Evidently the soldiers were not farmers; they were members of a professional, pan-European warrior class. They may even have been Europe’s first professional warriors.