This book presents a series of research on documentation practices and methods on eight Fuegopatagonian languages: Selk'nam, Haush, Alakaluf/Kawesqar, Yagan, Aonekko 'a'ien, Teushen, Gününün a Yajüch and Mapuzungun, carried out in Patagonia in the last third of the 19th century and up to the mid-20th century in a context of territorial expropriation and genocide of the pre-existing peoples. It also makes available unpublished documents in these languages that have been stored in repositories in Argentina, Chile, Germany and Italy. The publication seeks to make visible the work of the co-producers of the native peoples in the collection of information and methods of documentation of their languages, as well as the material conditions in which they developed. Undoubtedly, it values a little-known manuscript corpus, which at the time was shared by various scholars, objectified and extracted from its speaker communities, and thus contributes to consolidating an ethical position in interdisciplinary research work on the languages of the native peoples of the Fuegopatagonian region.