This book is the first experience of a comprehensive study of the Black Sea region based on data from sea maps of the late XIII - XVII centuries. The medieval portolan was the most accurate document of its time, containing a huge layer of information about various phenomena of reality and spatial representations of the era. Based on the analysis of the sea map, attracting a significant array of other materials (notes of travelers, notarial documents, annals, numismatic and archaeological data), the author seeks to create an adequate reconstruction of the political, economic, religious and ethnolinguistic situation in the Black Sea region.