This dissertation argues that early medieval palaces were not passive expressions of royal power, but agents in the constitution of new forms of political authority in post-Roman Europe. Focusing on palaces in the territory of the Roman Empire’s western provinces between the fourth and ninth centuries CE, this study adopts an interdisciplinary methodology to reinterpret how palaces were conceptualised by contemporaries, their role in early medieval societies, and how these characteristics changed over time. Drawing on the approaches of architectural history, archaeology, and social theory, I reinterpret palaces as simultaneously architecture designed to assert the ruler’s power and social spaces where the foundations and limits of political authority were negotiated. My investigation is divided into two co-ordinating parts with complementary analytical perspectives. In Part I, ‘Architecture and Space’, I show that a coherent ‘grammar’ of Late Roman palaces precipitously broke down following the disintegration of the Western Roman Empire. In its wake coalesced a new spatial configuration which responded to a changed lexicon of material display and to new ideals of legitimate authority. The architecture of the palace was not just a stage for ‘royal ideology’, however, but a medium of symbolic communication between the ruler and the elite that was given expression in ritual. In Part II, ‘Infrastructure and Landscape’, I draw on archaeological theories of landscape to examine the broader political structures in which palaces were embedded. In two case studies, I explore how royal authority was ‘spatialised’ through networks of palaces in the Ostrogothic kingdom of Italy and in the Frankish kingdoms of Gaul and Germany. By charting the fluctuations of these geographies over time, I demonstrate the instrumental role played by palaces in the reordering of political space in the post-Roman West.