This book develops a novel approach to the study of language, bringing it into dialogue with the latest geographical concepts and concerns and provides a comprehensive account of the geography of Welsh language analysing policy development, language use, ability and shift. The authors examine in particular: the different ways in which languages can be mapped; how geographical insights can be used to develop understandings of language use; the value of assemblage theory as a way of interpreting the social, technical and spatial aspects of language policy development; and the geographies that characterise institutional engagements with languages. This book will set a research agenda for the geographical study of language, developing a conceptual framework that will offer fresh insights to researchers in the fields of Applied Linguistics, Sociolinguistics, Minority Languages, Geolinguistics, and Public Policy.