Religious rituals are addressed to supernatural powers such as gods, spirits or ancestors.

They require a particular knowledge of the addressee's demands and forces and of the ritual practice itself.This knowledge is often controlled by certain groups or specialists (e.g., elders, shamans or priests) and may become a source of power.

Human sacrifice and other forms of ritual violence, such as auto-sacrifice (e.g., bloodletting) were widespread in the pre-Columbian Americas. Societies differed widely in their political and economic organisation, ranging from small mobile egalitarian bands of hunter-gatherers to complex urban states. In the last period before the European conquest major parts of the continent were claimed by two empires, the Inca in the central Andes (c. 1400-1532 ce ) and the Aztec in Mesoamerica (c. 1428-1521 ce), each with several million subjects.

Numerous artefacts related to ritual violence such as sacrificial knifes and axes have been found. Demarcated ritual spaces, typical architecture (e.g., temples) or outstanding environmental features (e.g., springs, caves, sink­holes and mountains) served as its stages. Ritual violence is prevalent in the iconography of pre-Columbian sculpture, on ceramics and other media. Early colonial ethnographic and linguistic sources and, in the case of Mesoamerica, epigraphic analysis of autochthonous writing systems point to indigenous understandings of the rituals. These data are enriched by the bio-archaeolo­gical study of human remains. The age, gender and geographic origin of a victim may be detected by osteological and isotopic analysis.

Information about ritual violence is often controversial and biased by normative or strategic considerations. Colonial and postcolonial discourses have frequently either exaggerated or downplayed such practices. Thus, the critical analysis and cross-checking of data from different sources are necessary. Methodological challenges have to be met to sort out myth, ideology, hearsay, observation, interpretation and actual behaviour. Contradictions between the sources are common and the cultural context is often deficiently documented or neglected. These problems are particu­larly acute for the egalitarian societies in the pre-Columbian Americas. In the following, we will therefore focus on ritual violence and human sacrifice in the ranked and stratified societies in the south-western and south-eastern culture areas of North America, in Mesoamerica and in the central Andes. The Aztec example will play a major role for several reasons: first, ritual violence and human sacrifice were particularly promi­nent in the Aztec empire. Second, various depictions of such ritual prac­tices can be found on pre-Columbian sculptures and in early colonial codices. Third, they are also referred to in eyewitness accounts of Spanish conquistadors. Fourth, the Aztec sacrificial complex was studied by early Spanish chroniclers, such as the mendicant missionaries Bernardino de Sahagun and Diego Duran. While the relevant information is relatively sparse for other Amerindian groups, these works offer pro­found and detailed historic and ethnographic descriptions of ritual violence and its mythological background.^{[763] [764]} The chapter will end with a brief comparison of Aztec and Inca human sacrifice and some general conclu­sions concerning the functions and meanings of ritual violence.