Core-periphery studies neglect early political doctrines. Different responses of emerging core-periphery relations in northern Scandinavia, Greenland, and Iceland can be understood in light of the political doctrine put forward as laws at an 1158 assembly by the German-Roman emperor and the political contemporaries of the papacy. The doctrine became a pattern across medieval Europe and defined ideas of imperial (royal) power versus that of the pope and the magnates, declaring the emperor supreme in ruling the country and maintaining law, order, and peace (i.e., embryonic elements of the later states). This doctrine accepted the Church as an independent political power. Royal duties were, according to the doctrine, to be financed by exclusively royal sources of income, some of which are visible in the archaeological record: minting, markets, towns, and various natural resources in “marginal areas”—such as the border areas between emerging territorial states. Reluctance (documented in Iceland) or ignorance (Greenland) boosted marginality, while the acceptance (northern Sweden) expanded centrality.