This dissertation shows how the discourse of the fetish emerged, in the formative moments of Iberian imperial expansion into the Atlantic, from the misrecognition of African religious practices and objects as witchcraft in merchant and missionary accounts. To do so, I analyze the refashioning of a medieval Iberian notion of witchcraft—hechicería in Spanish and feitiçaria in Portuguese—in the context of the expansion of Iberian empire into Brazil and West Africa, to accommodate what were perceived to be new magic techniques and magical objects. This concept form of witchcraft was particularly amenable to expansion, as already in its medieval version it encompasses a variety of mechano-magical techniques designed to harness invisible powers to material effect. It is, moreover, defined by its venal character—more akin to religious fraud or swindling than devil-worship—setting it apart from the more common European definitions of Satanic witchcraft. The power and the danger of this kind of magic, in the eyes of the Inquisition, had to do with the way it conflated making and making happen, claiming to be able to mechanically bend space and time through the fabrication of charms and amulets, thereby opposing a vision of the world where human fabrication can be generative to one of divine creation. It is in West Africa and the New World, in the trade-oriented writings of the early sailors and merchants, that the commercial component of feitiçaria achieves new importance and flourishes in the confusion of economic and spiritual regimes of value. In describing their West African trading partners and evangelical targets, the Portuguese called feitiçaria the veneration of what were perceived to be mere objects, called feitiços. In Brazil, enslaved Africans were targeted by the Inquisition for their attachment to feitiços, leading to the racialization of this form of witchcraft as they sought to deploy the invisible powers of feitiços for psychic and corporal protection.