Аннотация:In this article we shall discuss the category of “untranslatable” maps using the example of the manuscript maps of Japan drawn by Daikokuya Kōdayū (1751–1828), of which eight copies are known to date. These maps were initially created as cartographic images of Japan for “foreign” usage to be translated to serve the needs of the Russian state. However, the system of cartographic representation used by the Japanese author turned out to be untranslatable for the intended audience and, since it was not explained, remained incomprehensible. The maps were drawn during the author’s detention in Russia, as at this time and place he appeared to be the only knowledgeable native Japanese capable of producing a map of Japan. All the maps are large-format, coloured manuscripts. They resemble each other but are not identical. The failure of an audience trained in the modern Western cartographic tradition to understand the system of cartographic representation used in the maps by Daikokuya Kōdayū is the reason why these maps, despite all the effort expended in translating and commenting on them, were not recognized as documents of state importance, and do not seem to have had much influence on the contemporaneous mapping of Japan by Western scholars. The maps became Japanese “curiosities”. Daikokuya Kōdayū is widely known in Japan and Russia, and the story of his extraordinary life, in addition to arousing considerable scholarly interest, has attracted the attention of artists, making him the hero of novels, films, and even an opera. However, his dramatic history overshadowed his maps, studies of which are few in number, and all those that have been published to date are in Japanese.We regard these maps from the perspective of a historian of East Asian cartography interested in formal methods of map analysis. The eight maps by Daikokuya Kōdayū provide a simple case of map filiation, which can be used to test methods of its analysis. In this article we propose the first tentative genealogy of these maps, established by applying a few formal criteria.