Analysing linguistic diversity from a geopolitical perspective, this book studies the changing relations between language, power and territory in Europe in the process of European integration. It revisits the relations between territoriality, state formation, nation building and monolingualism in the evolution of the European modern state system. The impact of European integration on the building of a new configuration of territoriality, political institutions, and multilingualism and on the diverse existing configurations of language, power and territory in its 27 Member States is also examined. It shows how language and (national, supranational and transnational) political institutions constitute each other, and how territoriality and scale impact on this co-evolution. Critical geopolitics sheds new light on crucial issues linked to the changing language balance in Europe. A thorough analysis of discourses of monolingualism and multilingualism and related linguistic practices, enhances our understanding of Europeanisation. By critically assessing this "language politics" the book uncovers the contradictions between the EUropean rhetorics about multilingualism, the growing hegemony of English, the reinforcement of territorial official languages and the individual and collective strategies of Europeans to deal with linguistic superdiversity. In addition focusing on languages advances our understanding of critical geopolitics by showing how language choices are not only communication tools to convene meaning, but that they are in themselves bordering devices producing and organising space.