The Andean Late Horizon (ca. AD 1438–1532) was a period of exceptionally rapid and far-reaching cultural change. Over this short span of only a few generations, the Inka ethnic group established an empire that was greater in size than any other pre-colonial American polity. The Inka accomplished their expansion without the use of certain institutions (i.e., a standing army, formal writing system, monetary system, or price-setting markets) that the received anthropological wisdom has long held as being necessary preconditions to imperial expansion. Standard explanations of Late Horizon culture change tend to overemphasize the roles of environmental constraints, social evolution, and economistic motives. In this thesis, I analyze Inka expansion beginning with the assumption that “value” was an assessment of socially-integrating creative action, rather than of objects to be exchanged and accumulated (cf. Graeber 2001). I determine that the Inkaic Late Horizon was motivated by pursuits of “vitality,” or the capacity to effect change in pacha—an Andean concept of the world as a mutable coalescence of time, space, and matter. Vitality was not captured through the production or accumulation of goods, but through intensifying their production and circulation. I conclude that Late Horizon political economy in the Xauxa-Pachacamac axis can best be understood as a socially-stratified “gift economy” in which what was ultimately transferred were not objects, but vitality.