Endemic violence in a pre-Hispanic Andean community: A bioarchaeological study of cranial trauma from the Majes Valley, Peru.

Objectives: This study examines violence-related cranial trauma frequencies and wound characteristics in the pre-Hispanic cemetery of Uraca in the lower Majes Valley, Arequipa, Peru, dating to the pre- and early-Wari periods (200-750 CE). Cranial wounds are compared between status and sex-based subgroups to understand how violence shaped, and was shaped by, these aspects of identity, and to reconstruct the social contexts of violence carried out by and against Uracans.

Materials And Methods: Presence, location, and characteristics (lethality, penetration, and post-traumatic sequelae) of antemortem and perimortem cranial fractures are documented for 145 crania and compared between subgroups. Cranial wounds are mapped in ArcGIS and the locational distribution of injuries is compared between male and female crania.

Results: Middle adult males were disproportionately interred at Uraca, particularly in the elite Sector I. The Uraca mortuary population presents the highest rate of cranial trauma reported for pre-Hispanic Peru: 67% of adults present trauma, and among those, 61.1% present more than one cranial injury. Males exhibit significantly more cranial trauma than females and present a higher mean number of injuries per person. Elite males show the highest mean number of injuries per person, more antemortem injuries, and are the only ones with perimortem cranial trauma, bladed injuries, penetrating injuries, and post-traumatic sequelae. Both sexes were most frequently injured on the anterior of the cranium, while the proportion of posterior injuries was higher for females.

Discussion: The rate, intensity, and locational patterns of cranial trauma suggests the community was engaged in raids and/or war with enemy groups, some of which may have increased physical violence between community members. Engaging in violence was likely a prerequisite for burial in the elite sector and was bound up with the generation and maintenance of social status differences linked to male social life.