Early modern Iberian history has enjoyed renewed interest over the last 2 decades or so, with historians utilizing connected historical and global approaches to untangle interactions between various peoples within a vast empire. These studies have accounted for the unique social constructions within the Iberian world, and contended with questions regarding the political integration of Spain and Portugal during the Iberian Union (1581–1640). Scholars have attempted to complicate previous nationalistic interpretations of this period and looked at the institutional and cultural interactions within the Iberian Peninsula and its overseas territories. However, scholars have omitted serious examinations of Dom António's claim to the Portuguese crown during and after the dynastic crisis of 1580, as well as to the imperial and global dimensions of his candidacy. This article considers how the candidacy of Dom António and the Portuguese succession crisis can contribute to understandings of diplomatic interaction and more generally the negotiation of power in the Iberian world.