The Cold War border regimes between Romania and Yugoslavia were not only aimed at securitising the Romanian territory from any Western infiltrations, but also at actively imposing the party state, in physical and ideological form, antagonising and settling consensus among groups and individuals within the Romanian border area. The early Stalinist border regime established a harsh defence apparatus oriented both towards and beyond the country's territory, with multiple possibilities of action and subjection. In contrast with developments that led to the internalisation of a growing everyday feeling of the state and border's illegitimacy, the party's apparatus of culture produced visions of consensus, stability, and control at the frontier, in the context of an intense class struggle strengthened by alliances between borderlanders, party representatives, and the military. By analysing three fiction novels - La borna 203, Undeva pe Dunǎre (Alexandru Jar) and Iluzia (Ion Lotreanu) - the thesis explores different constructions (proletcult/socialist realist and modernist) of the frontier between Romania and Yugoslavia in two periods. The first period refers to the Romanian sovietisation and break-up of relations with Yugoslavia, as of the 1950's. The second period concerns the de-sovietisation of the 1960's and the re-enactment of good relations with Yugoslavia. Using actor network theory, as well as other theoretical inputs, the thesis follows the border along processes that attempt to objectify and 'close' it into a black box. Also, it points out the difficulty of representing the border and describes the attempts of 'opening' it. In the final part of the ethnographic chapter, the border is traced and analysed through processes that produce what I call here practices and imaginations of 'dwelling' and 'crossing', and their consequences for the border-entity, or actor-network. This final part, that uses interviews and fieldnotes collected during fieldwork on the border, brings us to the intrigue of the impossibility of closing the black box of the border. Along with the fiction novels that cover the early periods of 1950's and 1960's, the final ethnographic part, which is formed by retrospective narratives, mixes various spatiotemporal references, from the 1960's to 1989 and after. The thesis concentrates on a few aspects of border-making processes: the 'utopian' constructions of cross-border flows and control during the early period of absolute legal restrictions on crossing and the relations which border guards developed with local populations in their efforts to defend the 'Motherland'. In addition, by using fieldwork experience and certain stories from fiction novels, the thesis discusses dwelling and crossing as intersubjective engagements with cross-border flows and control with the mediation of an important event that generated a principal actant within the border-network - the construction of the Iron Gates dam. Combining fieldwork material and fiction works into an ethnographic piece, the thesis approaches its objects creatively and seeks to avoid the fixity and limitations of the metanarratives that bias the study of early expansion of the Romanian Workers' Party, and socialism, in general. Also, the thesis wants to be a contribution to the anthropological study of borders. In doing so, it advances the possibility of treating borders as becoming, never-quite-fixed entities, or actor networks, which can support dereifying frontiers as objects of inquiry and avoid the overemphasis on notions of culture, state, and territory which are common references in the existing social sciences literature and sometimes pose the risk of simplifying and reifying complex social relations and political processes.