This volume is an attempt to expound the current state of research into the past of the Basque language. This research has experienced two kinds of advance in recent years. First, more written records have been discovered, and the ones that we already knew have been more deeply studied. Second, since the 70s cross-linguistic typology has made huge progress in our knowledge of linguistic universals and grammaticalization paths. The purpose of this volume is precisely to provide an outline, comprehensible for Bascologists and diachronic typologists alike, of how these two aspects can help us to reconstruct, within the limits permitted by the principles of diachronic research, the main linguistic features of Common Basque (ca. 5th-6th cc. AD), Proto-Basque (ca. 3rd-1st cc. BC), and Pre-Proto-Basque.