Thousands of bones and hundreds of weapons reveal grisly insights into a 3,250-year-old battle

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A new analysis of dozens of arrowheads is helping researchers piece together a clearer portrait of the warriors who clashed on Europe’s oldest known battlefield 3,250 years ago.

The bronze and flint arrowheads were recovered from the Tollense Valley in northeast Germany. Researchers first uncovered the site in 1996 when an amateur archaeologist spotted a bone sticking out of a bank of the Tollense River.

Since then, excavations have unearthed 300 metal finds and 12,500 bones belonging to about 150 individuals who fell in battle at the site in 1250 BC. Recovered weaponry has included swords, wooden clubs and the array of arrowheads — including some found still embedded in the bones of the fallen. No direct evidence of an earlier battle of this scale has ever been discovered, which is why Tollense Valley is considered the site of Europe’s oldest battle, according to researchers who have studied the area since 2007.

Studies of the bones have yielded some insights into the men — all young, strong and able-bodied warriors, some with healed wounds from previous skirmishes. But details on who was involved in the violent conflict, and why they fought in such a bloody battle, has long eluded researchers.

There are no written accounts describing the battle, so as teams of archaeologists have unearthed more finds from the valley, they have used the well-preserved remains and weapons to try to piece together the story behind the ancient battle scene.

Now, a team of researchers studying arrowheads used in the battle has discovered evidence that it included local groups as well as an army from the south. These findings, published Sunday in the journal Antiquity, suggest the clash was the earliest example of interregional conflict in Europe — and raise questions about the state of organized, armed violence thousands of years ago.

“The arrowheads are a kind of ‘smoking gun,’” said lead study author Leif Inselmann, researcher at the Berlin Graduate School of Ancient Studies within the Free University of Berlin, in a statement. “Just like the murder weapon in a mystery, they give us a clue about the culprit, the fighters of the Tollense Valley battle and where they came from.”

Previous discoveries of foreign artifacts, such as a Bohemian bronze ax and a sword from southeastern Central Europe, and analyses of the remains have suggested that outsiders fought in the Tollense Valley battle. But the researchers of the new study were curious to see what clues the arrowheads would yield.

When Inselmann and his colleagues analyzed the arrowheads, they realized that no two were identical — not exactly shocking before the days of mass production. But the archaeologists could pick out key differences in the shapes and features that signified some of the arrowheads were not made within Mecklenburg-Western Pomerania, a state in northeast Germany that’s home to the Tollense Valley.

Inselmann collected literature, data and examples of more than 4,700 Bronze Age arrowheads from Central Europe and mapped out where they came from to compare them with the Tollense Valley arrowheads.

Many matched the style of arrowheads from other sites in Mecklenburg-Western Pomerania, suggesting they were locally made and carried by men who called the region home, according to the study.

But other arrowheads with straight or rhombus-shaped bases and side spurs and barbs matched those from a southern region that now includes modern Bavaria and Moravia, Inselmann said.

“This suggests that at least a part of the fighters or even a complete battle faction involved in Tollense Valley derive from a very distant region,” Inselmann wrote in an email.

Inselmann and his colleagues suspect it unlikely that the arrowheads were imported from another region to be used by local fighters. Otherwise, they would expect to find evidence of arrowheads within ceremonial burials in the region that were practiced during the Bronze Age.

A causeway that crossed the Tollense River, constructed about 500 years before the battle, is thought to have been the starting point of the conflict, said study coauthor Thomas Terberger.

Terberger, a professor in the department of prehistoric and historical archaeology at Germany’s University of Göttingen, has studied the site, a 1.8-mile (3-kilometer) stretch of the river, since 2007.

“The causeway was probably part of an important trade route,” he said. “Control of this bottleneck situation could well have been an important reason for the conflict.”

However, the fact that researchers haven’t found any clear evidence in the area of sources of wealth, such as mines for metal or places to extract salt, makes the trade route theory less likely, said Barry Molloy, an associate professor in the school of archaeology at University College Dublin. Molloy was not involved in the study.

“The causes of warfare were many, but it is likely in my view that this was about a group seeking to impose political control over another — an age old thing — in order to extract wealth systematically over time, not simply as plunder,” Molloy said in an email.

The exact scale and cause of the battle remain unknown, but the remains and weaponry found so far suggest more than 2,000 people were involved, according to the study. And researchers believe that more human bones are preserved in the valley, which could represent hundreds of victims.

The 13th century BC was a time of increased trade and cultural exchange, but the discovery of bronze arrowheads across Germany has suggested it was also when armed conflict arose.

“This new information has considerably changed the image of the Bronze Age, which was not as peaceful as believed before,” Terberger said. “The 13th century BC saw changes of burial rites, symbols and material culture. I consider the conflict as a sign that this major transformation process of Bronze Age society was accompanied by violent conflicts. Tollense is probably only the tip of the iceberg.”

The new study also points to the placement of arrow injuries found on remains buried at the battle site, which suggests that shields may have protected warriors from the front, while their backs were left exposed.

The research drives home the importance of archery on the battlefield, which has often been underestimated in previous studies of Bronze Age warfare, Molloy said.

“This is a really convincing study that uses routine archaeological methods to great effect to provide insight into the nature of this key prehistoric battle site, with regard to aspects of battlefield actions and the participants involved,” he said. “The authors make a robust case that there were at least two competing forces and that they were from distinct societies, with one group having travelled hundreds of kilometers. That is a crucial insight into the logistics behind the armies involved at Tollense.”

The large scale of battle has researchers rethinking what social organization and warfare were like during the Bronze Age.

“Were the Bronze Age warriors (organized) as a tribal coalition, the retinue or mercenaries of a charismatic leader — a kind of ‘warlord’ — or even the army of an early kingdom?” Inselmann said.

For a long time, researchers argued that Bronze Age violence was a small-scale affair involving tens of individuals from local communities, but Tollense blows that theory wide open, Molloy said.

“We have many sites where we find evidence of mass killing and even slaughter of whole communities,” Molloy said, “but this is the first time that the demographics of the dead are those we can reasonably argue were warriors and not, for example, whole families migrating.”

Bronze Age societies built fortified settlements and smiths to forge weapons, but Tollense shows that both were more than just displays of power, he said.

“Tollense shows us that they were also created for very real military purposes including full scale battles that involved armies on the march, moving into hostile lands and waging war,” Molloy said.