The birth of war: an archaeological survey concludes that warfare, despite its malignant hold on modern life, has not always been part of the human condition

Natural History, July-August, 2003 by R. Brian Ferguson

Evidence from Europe offers a clear window into pre-agricultural practices. There is no firm evidence of war for thousands of years during Paleolithic times--though some scholars see suggestive indications in a few places. After 10,500 years ago, however, as the population of foragers became larger and more settled, several sites show individual violence, and others show the more collective casualties that signal war. Still, the evidence of violence is present at only a small minority of all excavated sites. Beginning around 6,500 years ago, however, fortifications, embedded points, and even clear signs of village slaughters become common. By the Bronze Age, 2,000 years later, war and weaponry had become a veritable cult.

North America presents a highly complex and regionally divergent picture. Kennewick Man, a skeleton unearthed in Washington state and considered between 7,500 and 9,200 years old, contains an embedded stone point. But because the skeleton is an isolated find, the injury is difficult to interpret. On the coast of the Pacific Northwest, skeletal trauma and other signs of conflict begin to appear about 4,200 years ago in the northern regions, but show up farther south only many centuries later. Many of the excavated skeletons from the ancient eastern woodlands show signs of violence. In a few cases multiple individuals were involved, including one site in Florida dating from more than 7,000 years ago. Still, such cases remained extremely unusual until 5,000 years ago. In the southern Great Plains, out of 173 skeletons reported from before A.D. 500, only one indicates homicide, a woman killed by two blows to the head. The first clear evidence of warfare in the Southwest dates from less than 2,000 years ago, and it is quite dramatic. At least two-thirds and perhaps all of the ninety-odd individuals interred in a cave in southern Utah were killed.

Roughly speaking, that is where my survey leaves off. But my preliminary work leads me to expect no major surprises from Africa, Mesoamerica, Oceania, or South America. In sum, if warfare were prevalent in early prehistoric times, the abundant materials in the archaeological record would be rich with the evidence of warfare. But the signs are not there; here it is not the case that "the absence of evidence is not evidence of absence."

So how did peaceful tribal peoples of the distant past turn into the war-prone societies observed in recent centuries? Specific causes are elusive, but I see five preconditions that, in varying combinations, contributed to the onset of warfare in prehistoric times. One was a shift from a nomadic existence to a sedentary one, commonly though not necessarily tied to agriculture. With a vested interest in their lands, food stores, or especially rich fishing sites, people no longer could walk away from trouble.

Another precondition was a growing regional population and probably, in consequence, more competition for resources. Third was the development of social hierarchy, an elite, perhaps with its own interests and rivalries. Fourth was an increasing long-distance trade, particularly in prestige goods: something else worth fighting over. Finally, the first appearance or later intensification of war was often associated with a severe climatic change that broke down the subsistence base.