Questions related to the origin and history of the Basque language spark considerable interest, since it is the only surviving pre-Indo-European language in western Europe. However, until now, there was no readily available source in English providing answers to these questions or giving an overview of past and current research in this area. This book is intended to partly fill this void. The book contains both state-of-the-art papers which summarize our knowledge about particular areas of Basque historical linguistics, and articles presenting new hypotheses and points of view based on hard evidence and careful analysis. All contributors to this volume have demonstrated expertise in the topic within Basque historical linguistics that their chapter addresses. Two classical articles by the late Luis Michelena are included in English translation. In addition, the book includes studies on diachronic phonology, morphology and syntax. The relation of Basque to other languages is also investigated in a couple of chapters.