The end of the Neolithic and the beginning of the Early Bronze Age was a time of processes governed by profound cultural transformations. These fundamental changes involved the emergence of new social and economic structures related to pastoralism and the resulting increased mobility of human groups. This must have brought about various inter-group conflicts, arising, for example, from competing over the best pastures. At the same time, it should not be ruled out that, in the then customs, aggressive behaviour had been integrated into the canons of existence, thus leaving a deep mark on the generally accepted ethical norms. The basic set of instruments found in graves, notably military in character and consisting of an axe, a knife or a dagger and archery equipment, provides some evidence in this respect. This was a period when the need for a strong emphasis on self-awareness and group self-identification was an important factor, and so was the desire to distinguish oneself from the surrounding cultural environments. In archaeological sources, the above-mentioned trends in cultural behaviour are manifested especially in artefacts of military character, flint arrowheads in particular. A significant part of the Late Neolithic and Early Bronze Age finds of flint arrowheads comes from graves (Fig. 1, 7, 8). These artefacts are most often interpreted, probably rightly in most cases, as part of equipment accompanying the deceased. However, a detailed observation of the contexts in which arrowheads are found in graves has repeatedly revealed that their interpretation is not always unambiguous (Fig. 2–5). Sometimes, the context clearly indicates that the finds can be seen as a kind of corpus delicti – the cause of death of the buried persons (Fig. 6). The aim of this article is to present selected sources from the area of Poland that exemplify the research problem indicated in the title of this paper.