Known in Norwegian historiography as Norgesveldet , the realm consisted of the mainland Norwegian kingdom and a range of island communities at Scotland s northern and western seaboards, as well as the Faeroes, Iceland and Greenland. Within this national historiographic tradition, Norgesveldet is often portrayed as a kind of Norwegian empire. The aim of this project has been to elucidate the relationship between Norwegian kingship and the Crown s tributary lands in the west and the ways in which kingship influenced sociopolitical developments at the margins of the realm. The Scandinavian frontiers, which were never fully integrated into Norway during the Middle Ages, have also figured into this project. Working from the contention that Norgesveldet never developed as a Norwegian empire, we have elected to refer to The Realm of Norway and its dependencies as the Norwegian king s insular realm . In doing so, we challenge the Norwegian national tradition. As twenty-first century observers, we have distanced ourselves from the national paradigms of the nineteenth century. Additionally, because the communities at the margins of the realm were later enveloped in other kingdoms and developing states in the British Isles and Scandinavia, our research has led us to look beyond Norwegian historiography and to address other national historiographic traditions as well. Rex Insularum encompasses the results of the transnational project The Realm of Norway and its dependencies as a political system c. 1270 1400 , financed by the Research Council of Norway. «Rex Insularum er eit praktverk som naturleg nok er sjøsett i det året vi feirar at Grunnloven er 200 år.» - Karsten Alnæs, Dag og Tid «Den foreliggende bog er en nydelse at blade i, fyldt med oplysninger og ideer for læge og lærde, og den opfordrer til at tænke videre og arbejde videre.» - Kurt Villads Jensen, Historisk Tidsskrift «A seminal work of outstanding scholarship.» - Midwest Book Review