The First World War brought about social, political and national changes leading to the collapse of existing multinational monarchies (Russia, Austria-Hungary and Germany). This caused the reshaping of the political map of Eastern and Central Europe. Based on the example of a few selected nations - Poland, Ukraine, Belarus, Lithuania and Latvia - the authors discuss various aspects of the state reorganisation of Eastern and Central Europe. Such issues included the concept of borders, the formation of competing political centres, diplomatic efforts on the international arena, armed combat over borders, the role of France, Great Britain, Soviet Russia as well as Poland in creating a new balance of power in the region, and the provisions of the Versailles and Riga conferences.