Primitive society was not driven by war, scientists believe.
Researchers from Abo Academy University in Finland say that violence in early human communities was driven by personal conflicts rather than large-scale battles.
They say their findings suggest that war is not an innate part of human nature, but rather a behaviour that we have adopted more recently.
The study is published in the journal Science.
Patrik Soderberg, an author of the study, said: "This research questions the idea that war was ever-present in our ancestral past. It paints another picture where the quarrels and aggression were primarily about interpersonal motives instead of groups fighting against each other."
Motives for murder
The research team based their findings on isolated tribes from around the world that had been studied over the last century.
Cut off from modern life and surviving off wild plants and animals, these groups live like the hunter gatherers of thousands of years ago.
"They are the kind of societies that don't really rely on agriculture or domestic animals - they are primitive societies," explained Mr Soderberg.
"About 12,000 years ago, we assume all humans were living in this kind of society, and that these kind of societies made up about for about 90% of our evolutionary path."
Using the modern tribes as an analogy for earlier society, the researchers looked at cases where violent deaths had been documented.
They found 148 such deaths but very few were caused by war.
"Most of these incidents of lethal aggression were what we call homicides, a few were feuds and only the minority could be labelled as war," Mr Soderberg said.
"Over half the events were perpetrated by lone individuals and in 85% of the cases, the victims were members of the same society."
Most of the killings were driven by personal motives, he added, such as family feuds or adultery.
The researchers admitted that modern communities were not a perfect model for ancient societies, but said the similarities were significant and did provide an insight into our past.
Mr Soderberg said: "It questions the idea that human nature, by default, is developed in the presence of making war and that war is a driving force in human evolution."
Instead, he thinks that war may have developed later.
As the hunter gatherers made the transition to farming, groups became more territorial and with a more complex social structure.
"As humans settled down, then war becomes more dominant and present. For these primitive societies, war has not yet entered the picture," he added.