ENThis article, relying on the existing historiography and the primary sources (periodical press, programmes of political parties, correspondence, educational literature, maps) at the end of the 19th c. - the beginning of the 20th c. not only briefly discuss the territorial image of Poland dominating in the Polish discourse, but pays particular attention to those aspects of the problem, which have so far received less attention from the researchers, namely: the image of Lithuania as part of the "borderlands" and an integral part of Poland; the mental map, found in the Polish discourse in Lithuania; as well as how the territorial images of Poland created by the Polish elite were used in the nationalization of the masses, above all - in the former lands of the Grand Duchy of Lithuania (GDL). This article claims that at the end of the 19th c. - the beginning of the 20th c. in the Polish discourse there was almost no competition between the different conceptions of the territorial image of Poland. The territorial concept of Poland, relying on historical, economic, civilizational, geographic and power arguments, covering also the former GDL lands, became normative, while those of other concepts were heavily marginalized. Such a mental map dominated not only in the ethnic Polish core, but also in the Polish speaking society of the former GDL lands. Polish nationalism used a similar motivation also in indicating the western border of Poland, an important difference was only that in the West they also still relied on the ethnographic argument. Meanwhile, alternative conceptions, like the one of Czesław Jankowski designating the future of Poland only within its ethnographic borders, were marginalized. Moreover, in the case of Jankowski that was a dictated by conjuncture (i.e. tactical) proposal, when he also considered the ideal of the restoration of "historic Poland", hence with Lithuania. [...]. [From the publication]