Violence was a reality of life in early medieval Ireland (AD 400–1200). Its omnipresence is indicated from numerous narratives of regicide, mortal conflicts, battles and warfare that survive in ancient myths, legends and annalistic accounts. The archaeological evidence of violence and conflict is mainly identified in the osteoarchaeological record, and approximately 13% of all skeletal populations from excavated early medieval cemeteries in Ireland have shown evidence of weapon trauma. This study considers the osteological representation of violent deaths in two contemporaneous Irish skeletal populations dating to this period: Mount Gamble in County Dublin and Owenbristy in County Galway. This analysis involves assessing the different anatomical regions of the body for evidence of lesions that can be attributed to weapon trauma. The results indicate that these populations are likely to have been exposed to violence under differing circumstances; the evidence suggests that the individuals from Mount Gamble may have been well equipped or skilled at interpersonal battle, in contrast to the majority of individuals from Owenbristy who may have been unprotected and unprepared. The presence of two adolescents and two adult females amongst the victims from the latter population gives insight into a wider social dimension of weapon trauma in early medieval Ireland. There is also evidence of postmortem mutilations and decapitations, which reflect ritualistic aspects of violence. Copyright © 2012 John Wiley & Sons, Ltd.