In a study on the occurrence of trauma in prehistoric graves in Central Europe, evidence of violence over a period of more than 6000 years is presented diachronically for the first time. Ups and downs in the trauma sequence are recognisable in over 23,000 graves. Comparing it to our proxies for social organization of prehistoric societies, an inverse relationship appears: the higher the levels of social inequality are the lower are the signals of violence. We interpret this as an expression of a a monopolisation of violence through political power. In addition to fluctuations in the intensity of violence, the long-term trend indicates an overall reduction in violence at least until the early modern period.