Hadrian’s Wall and subsequent Roman frontier systems demonstrate that borders in antiquity operated less as fixed demarcations than as dynamic zones of interaction in which conflict, exchange, and hybrid forms of identity emerged. Across Late Antiquity and the early medieval period, societies along these frontiers integrated Roman and local traditions, generating complex, situational identities embodied by figures such as Clovis and Theodoric. Such premodern borderlands—characterized by fluidity, permeability, and cultural intermingling—stand in marked contrast to the linear, exclusionary borders consolidated after Westphalia and subsequently disseminated worldwide through imperial expansion. Although many twentieth-century boundaries imposed by great powers precipitated displacement, violence, and authoritarianism, borders have also served as frameworks for cooperation. Historically, frontiers functioned most productively when approached as negotiated spaces capable of sustaining coexistence.