The ritualisation of violence in Iron Age Europe has long been seen through the distorting lens of classical literary sources. Signs of perimortem trauma and the complex processing of human remains have typically been seen as evidence for Druidic sacrifice or the ‘Celtic cult of the head’. This chapter presents a more anthropological perspective, drawing analogies with societies documented through the ethnographic literature. Evidence for ritualised killing in the Iron Age comes from bodies found preserved in peat bogs, who suffered extremely violent deaths. Similarly, complex killings are represented by skeletal evidence from archaeological sites ranging from small settlements to large religious complexes. Despite differences in scale, similar cosmological principles underlie these sorts of practices across the Continent. Particularly common is a concern with the removal, curation and display of the human head; rather than representing a singular ‘cult of the head’, however, headhunting was a complex and recurrent practice that altered its character and meaning through time. The ritualisation of warfare is also implicit in the design of major hill forts and oppida. Overall, the archaeological evidence suggests that ritualised violence was a core element of the religious and cosmological beliefs that underpinned social relations in Iron Age Europe.