Boundaries of states are often taken as a given although they seem, in not a few instances, to be quite arbitrary. Their origins and changes through the centuries need to be examined and interpreted in order to explain why some state boundaries are frozen (often for tiny states) whilst others are highly volatile. The paper introduces and discusses a book by Luigi Tomaz concerned with Italy's eastern borders I confini dell'Italia in Istria e Dalmazia, Edizioni Think ADV, Conselve, PD, 2007). Tomaz thoroughly traces the history of Italian boundaries on the eastern shores of the Adriatic, particularly of the boundaries in Istria and Dalmatia, and contends that for almost two millennia these territories were, for the most part, a natural appendix of the Peninsula and that this sea (named in the old maps 'Gulf of Venice') was actually an Italian gulf. Main emphasis is given to the fact that strong and steady linguistic, political, economic, religious, ethnic and cultural ties had linked - as a consequence also of two-way migration flows across the sea - the inhabitants of the two opposite seaboards. The paper's approach to the subject involves some preliminary reflections on the very concepts of Nation and State as these two terms are commonly considered near-synonyms and are often used interchangeably. They have, instead, definitely different meanings. The meaning of State is clear. Nation, instead, is an ambiguous term; it doesn't overlap with State and may be defined by a variety of different criteria. Once a set of fundamental parameters designed to define what can be considered a Nation, has been selected (according, however, to personal views) and established, stateless nations as well as nation-less states may be easily detected by studying a world map. Last two centuries have witnessed large-scale map redrawing also in Europe mainly because of winners taking, in peace settlements, war booty from defeated countries. On the other hand, artificial states have been sometimes unified or, instead, broken up. Secessions of one country from another or of a region from the rest of the country may occur also spontaneously when borders do not match a division of nationalities. Furthermore, mergers of countries that are geographically close as well as secessions of a region from the rest of the country may be the outcome of purely economic factors: the latter, perhaps, according to some authors, might be, in a near future, the case of some territories of Northern Italy if the central government in Rome will not manage to cut down the debt burden by reducing substantially wasteful public expenditure. Often, but not always, national borders' changes have reflected redrawing of state borders. Geopolitical and economic factors affecting changes of nation and state borders are analysed and discussed at the end also by mentioning specific examples.