Geopolitics and Poland's Foreign Policy offers a comprehensive examination of how the Intermarium continues to influence Polish foreign policy. The Three Seas Initiative (TSI) in Eastern Europe was announced in 2016 as a flagship project of Polish diplomacy. In this book, the author analyses the TSI in the context of the Intermarium and demonstrates its relevance and implications for Polish foreign policy today. The book traces the emergence of the Intermarium in Polish foreign policy debates between 2005 and 2021. Through thematic analysis, the book identifies three main discourses in which the Intermarium is invoked for different purposes: Regional Hegemony, the Bridge, and New Paradigm. Each of these discourses uses the Intermarium to promote, legitimise, naturalise, or depoliticise different aspects of foreign policy. The author also examines how the Intermarium is used as a tool in political competition, defining the boundaries of legitimacy for actors in public discourse. This book will be a valuable resource for researchers of Eastern European politics, EU politics, international relations and foreign policy. It sheds light on the nuances of foreign policy decisions and political dynamics in Poland, as well as providing detailed discussions on the use of the Intermarium concept and the recent TSI policy project.