While structural models of empire have recently re-emerged in the theoretical debates in the field of International Relations, a lack of attention has been paid to peripheral actors therein. This is particularly true for the analysis of the peripheries’ relations with polities outside the imperial structure of which the peripheries are a part. In this article, I build a framework to better understand how these extra-imperial ties are translated into peripheral positional power. This framework is constructed on the basis of three core arguments. First, to theorise peripheral power, peripheries need to be positioned in networks outside the imperial structure. Second, the positional power of peripheries depends on the quality of the ties they have to external actors. Peripheries with dense and exclusive ties to external actors are more powerful than those with only sparse and non-exclusive ties. Third, from the different combinations of density and exclusivity arise not only variations in positional power, but also the likely strategies that are engaged in forming alliances with external actors. These logics are illustrated through the study of two cases of the diplomacy of decolonisation: the American Revolutionary War and the Angolan War of Independence.