ABSTRACT The objective of this article is to reflect on the connections between early modern Spanish empire building and expansionism by Christian principalities during the medieval period. The core argument, which is, by necessity, reductionist owing to the brevity of this article, is that while late medieval / early modern attitudes about conquest and world domination drew heavily on the history, models, and practices of earlier centuries, the ideology of empire that emerged from the later fifteenth century was distinct in two primary, interrelated respects. First, the increased political fragmentation within Christian-ruled lands intensified the more localized, inward-looking dynamic of the territorial struggles against Muslim regimes that contrasted with the more global outlook of later medieval and early modern Christian imperialism. Second, the distinct ideologies of these sometimes coordinated but often competitive earlier expansionist efforts were founded upon different justificatory conceptions of sacred and secular history that, again, were, in essence, much more peninsular in their orientation.