A model of late pre-Inka political geography of the region surrounding Cajamarca, in the north highlands of Peru, is presented. This model, based on ethnohistoric data and archaeological research, can be projected back through time to help delineate the culture history of the Cajamarca ethnic group. Several chiefdoms emerged during the Late Intermediate period, following a time of sociopolitical disintegration. The region that became the Inka province of Cajamarca had been occupied by five or six chiefdoms during the latter part of the Late Intermediate period. The data are equivocal on the subject of whether political centralization had developed in the region before the Inka conquest, but suggest that at least some form of confederation existed. Comparison with other regions of the Peruvian Highlands reveals that the Cajamarca ethnic group was modest in population, but controlled a very large area. Other groups, such as the Wanka and Lupaqa, appear to have been undergoing a similar process of sociopolitical centralization. The Inka reorganized the region upon its incorporation into the empire, creating an economic and religious center for several surrounding provinces.