The article focuses on the role and place of toponyms in the medieval Japanese political culture. The toponym can be considered as a hyperlink, “clicking” which reveals an endless chain of general cultural, historical, and literary images, events, and phenomena. Place name study requires a multidisciplinary approach. The insularity of the Japanese territory, terrain features, prevalence and sustainability of animistic beliefs contributed to the fact that the exact localization of an event or phenomenon took on special significance. A detailed address of an event or phenomenon most often consists of toponyms relating to a province, county, village or some particular place, which almost always makes it possible to find the specified object on a geographical map. Moreover, once introduced into the context of culture, geographical locations become places of worship, sources of inspiration for many generations and are rarely subject to change. Toponyms are an integral part of the names of deities, emperors and their family members. Place names were also important in determining and fixing the boundaries of the state. Probably, for the first time in the Japanese literary tradition the geographical area of the entire archipelago, except for the remote north-eastern part, was referred to in the oldest existing anthology of the Japanese poetry “Manyoshu” (dated by the second half of the VIII century). This article presents a detailed analysis of the provenance and use of toponyms making up the cultural and historical image of the country, its name (Yamato - Nihon), and the name of the archipelago’s highest mountain (Fuji). Also, as an example, we examine the toponym for a barrier (Shirakawa), the site which is currently little known, though once it used to be an important element of the medieval state political and administrative structure. The toponym as a type of proper names is inherently conservative, which allows it to be the custodian of historical information, to be an indicator of time in the written culture, that is, using the term coined by M.M. Bakhtin, to shape a chronotope of culture. The geographical certainty characteristic of the insular mentality and the correlation thereof with the imperial myth that has been one of the Japanese political culture’s foundations right down to the twentieth century, have become the grounds for the increased attention to the cultural tradition toponymy.