This book examines ethnoterritorial conflict and reconciliation in Ireland from the 1916 Rising to Brexit (2021), including the production and consequences of the island’s two distinct political units. Highlighting key geographic themes of bordering, unity, division, and national narratives, it explores how geopolitical space has been employed over time to (re)define divided national allegiances throughout Ireland and within Irish–British relations. The analysis draws from in-depth interviews and archival research, and spans supranational, state, municipal, neighborhood, and individual scales. The book pays particular attention to uneven power structures, statecraft, perceived truths, lived experiences, reconciliation efforts, and renegotiations of national narratives in the production of symbolic landscapes, divided cities, and "shared" space. An Introduction to the Geopolitics of Conflict, Nationalism, and Reconciliation in Ireland provides readers with an analysis of geopolitical power relations and different spatial productions of conflict and peacebuilding in Ireland. Offering deeper understanding of these historic and contemporary geopolitical intersections, this book makes a valuable contribution to the fields of Political Geography, Border Studies, Irish Studies, European Studies, International Relations, Cultural Geography, and Regional Studies.