Through the interrogation of the Jinjuseong Fortress in Jinju, South Korea, the connections between nationalism, memory studies, and the role of the built environment within international relations can be better understood. This thesis attempts to dissect the presentation of the Korean nation at this site as a continuous, inevitable nation and its implications for South Korean international relations. In looking at four specific sites within the fortress that have been added over the past 400 years, the Changyeolsa Shrine, the Sites of Nongae, the Patriot’s Altar, and the Jinju National Museum, the continuous and iterative development of a Korean collective memory through the built and memorial environment is shown. This iterative process has allowed these entities to work with one another to create a network of memory infrastructure which has merged the distinct memories contained by each site into a unified collective memory. Untangling this web of memorialization presents an opportunity to challenge the narrative presented at this place. By parsing out the history of this fortress and the sites that reside within it, the artificial continuity of the Korean nation between the historic, the contemporary, and the future is broken. Through analyzing the Jinjuseong Fortress, Korean and East-Asian perspectives are elevated within the fields of nationalism, memory studies, and the built environment, providing a deeper and more robust understanding of processes that define identities of and relationships between different states. This analysis exposes the manufactured quality of the national collective memory presented at this South Korean site and, with it, exposes the fallibility of a national memory. This artificial national memory serves as the basis for South Korean ontological security and, in challenging this basis, this thesis attempts to revisit contemporary understandings of historic antagonisms that underlie the relationship between South Korea and Japan today. In all, this thesis attempts to engage nationalism, memory studies, and the built environment with international relations through the lens of ontological security to revisit the past in an attempt to create a future in which memories and perspectives of one group can ultimately engage and reconcile with narratives of others.