The book offers a historical and methodological update of founding historical themes and moments, and a methodological review more than ever necessary of current interpretations of the History of Sardinia between the Early Middle Ages and the Modernity from an identitarian point of view. And that by means of a greater interaction between History, History of Art, Geography, Archaeology and Architecture. Sardinia has been taken as a case study due to its island nature, with boundaries clearly determined by Geography and, moreover, by its extremely conservative nature. The authors¿ aim is to provide scholars with new data and new reading keys to interpret Sardinian History and its Cultural Heritage. Both strongly conditioned by the permanence of Sardinia in Roman and Byzantine orbit, lato sensu, for more than a millennium (3^rd c. b.C - 11^th c. a.C) and by two other important elements: only about 80 years of a virtually irrelevant Vandalic domain and no Muslim lasting settlements throughout the High Middle Ages, not so far decisively confirmed by Archaeology.