Fundamental features of the early modern Atlantic -like the slave trade, the rise of experimental science and long-distance commerce, and the proliferation of religious confessions -were transnational in character. This essay surveys recent work in the field, emphasizing emerging scholarship on the hybrid nature of the Atlantic world. Yet for hybridity to work as a useful analytical category, we need to do away with the narrative of "Northwestern Europeanization" as the normative model. We explore how ecology and place, science and medicine, and diasporic or extra-national groups like smugglers, Jews, and slaves helped create an Atlantic that was defined more by its cross-cultural encounters, local contexts, and mixed identities than by the power of European states.