Until the mid-14th century, the Polish-Ruthenian border ran along Wisłoka river. It was abolished when Red Ruthenia was incorporated into Poland. However, this area remained a Polish-Hungarian borderland even after the fall of the Polish state in the 18th century, retaining the character of a political borderland to this day. Since the Middle Ages, the indicated region, also due to its borderland character, became the target of successive or parallel colonization/migration waves, to mention the largest: German and Polish associated with the incorporation of Red Ruthenia, which created a cultural group of Deaf/Forest Germans in the existing settlement void, Wallachian – which lay at the roots of the Lemkos, and Jewish. In this way, the former Polish-Ruthenian-Hungarian borderland became a cultural, religious, and ethnic borderland, retaining this character until the mid-20th century. These exemplary great migrations in the study region have been accompanied since the Middle Ages by ordinary, everyday migrations related to the movement of the rural population to other villages, to towns and cities, looking for work, fulfilling religious needs, also cross-border between Poland and Hungary. Great migrations were accompanied by the creation of a specific spatial settlement structure (linear forest villages), while small ones were accompanied by the construction of appropriate communication and transport infrastructure and the development of a specific borderland culture, also expressed in works of official, sacred, and folk art. At the same time, Forest Germans were in constant motion under the constant pressure of the natural environment – the raw Carpathian nature, subject to changes resulting from global processes, attracting and pushing further migrants. The most general aim of the project is to recognize and understand mobility structures of Forest Germans in “the longue durée” in the Carpathian demanding and changing environment in the Little Ice Age. The result of the project will be a multidisciplinary and interdisciplinary panorama of human-environment relations in “the longue durée” of 600 years (from the Middle Ages to the early 20th century) on the difficult Carpathian political and cultural borderland. At the same time, it will be a classic geographical synthesis combining the analysis of human spatial behaviors in the geographical environment, trying to answer the fundamental questions: where do we come from?, who are we?, where are we going?. Finally, we should know more about the ethnogenesis and culture of the Forest Germans, their connections with other national and cultural groups in Central Eastern Europe, their functioning in space (mobility, settlement structures), environmental variability and evolution, inc. climate, in Forest Germany, and the human-environment relationship there. The implementation of such a large-scale project will only be possible thanks to the cooperation of specialists representing various disciplines of knowledge, i.a. geographers, historians, cartographers, anthropologists, geneticists, dendrochronologists and palynologists. Importantly, the selected region is also poorly researched in the scope indicated in the application, and therefore the project has a chance to enrich our knowledge about the Carpathians in the past and at present.