In the most recent decade, the thematic field of frontiers and identity, especially the interconnection of both concepts, has belonged among the symptomatic phenomena of Czech historiography. As a result, coordinated and mutually coherent works have been developed, which, in addition to research, also involved activities in the areas of historical education, the transfer of knowledge and international cooperation. It is one of the fields in which Czech historiography has been actively involved in international scientific communication, and in addition in a partly coordinator role. With the emergence of the new theme of frontiers and identity, Czech historiography relatively quickly responded to the developments in international scientific reflections. This contribution deals with reasons for this newly arisen focus, albeit neither the theme of frontiers nor the issue of identity were entirely novel categories of historical thought in the 1990s and in later years. However, at this time they attained rather new connotations and relevant meanings and in connection with this the manner of treating the subject matter has also changed. Post-modernist challenges – in terms of post-modern perspectives and critical responses to them – have become decisive preconditions of this phenomenon from the last stages of the 20th century. This contribution follows the formation of new concepts of collective identities, frontiers and space, especially in their mutual interconnection. At the same time attention is paid to mutual connections between international and Czech reflections. At its conclusion, comments are devoted to the special section of the 10th Congress of Czech Historians in Ostrava, which dealt with these issues.