This article addresses the bioarchaeological evidence for Inca warfare through an analysis of 454 adult skeletons from 11 sites in the Inca capital region of Cuzco, Peru. These 11 sites span almost 1000 years (AD 600–1532), which allows for a comparison of the evidence for warfare before the Inca came to power (Middle Horizon AD 600–1000), during the time of Inca ascendency in the Late Intermediate Period (AD 1000–1400), and after the Inca came to power and expanded throughout the Cuzco region and beyond (Inca Imperial Period, AD 1400–1532). The results indicate that 100 of 454 adults (22.0%) showed evidence of cranial trauma. Of these, 23 individuals had major cranial injuries suggestive of warfare, consisting of large, complete, and/or perimortem fractures. There was scant evidence for major injuries during the Middle Horizon (2.8%, 1/36) and Late Intermediate Period (2.5%, 5/199), suggesting that warfare was not prevalent in the Cuzco region before and during the Inca rise to power. Only in the Inca Imperial Period was there a significant rise in major injuries suggestive of warfare (7.8%, 17/219). Despite the significant increase in Inca times, the evidence for major cranial injuries was only sporadically distributed at Cuzco periphery sites and was entirely absent at Cuzco core sites. These findings suggest that while the Inca used warfare as a mechanism for expansion in the Cuzco region, it was only one part of a complex expansion strategy that included economic, political, and ideological means to gain and maintain control. Am J Phys Anthropol, 2011. © 2011 Wiley-Liss, Inc.