The historical focus of this dissertation is the emergence and consolidation of polities along the southwestern fringes of the central highlands of Sri Lanka between the twelfth and fifteenth centuries. Earlier debates about the “drift” of political authority from the imperial capitals of the north to the little kingdoms of the southwest relied on tropes of medieval decline and models of political disarticulation typical of feudalist historiography. This approach is partly understandable in the Sri Lankan context given the palpable anxiety that runs through Pali- and Sinhala-language chronicles over perceived threats to the privileged relationship between Lankan kings and Buddhist monastic orders. However, in reading elite chronicles as objective accounts of prevailing historical conditions, the historiography of Sri Lanka has been overdetermined by the normative requirements of Buddhist kingship. It has thus conceptualized politics during the “Drift to the Southwest” in decidedly regressive terms, uncritically reproducing chronicle accounts of the destruction of a Buddhist state by successive South Indian military invasions and cultural concessions to new Hindu overlords. This dissertation takes as its point of departure the notion that these anxieties are best understood as responses to transformations often theorized at levels ‘below’ the state. I argue that these social transformations were generative of local and regional sources of political dynamism. Central to the constitution of political power was the slow incorporation of regionally mobile groups like warrior bands, merchant guilds, and caste sodalities into evolving socio-political hierarchies. While prior Lankan scholarship has narrowly conceived of these groups as proxies of theistic South Indian empires, and thus inherently antagonistic to the religiously defined interests of the Buddhist Lankan state, I argue for continuity between the two. Through an examination of these social types as the key historical agents behind changes to what it meant to represent oneself as a Buddhist king, I reconstruct over the longue durée the ways in which these aspiring groups negotiated the structural constraints of political hierarchy. In the process, they reshaped understandings of themselves as collective agents, as well as their localities as sites from which individual political careers could be launched.