Fernand Braudel launched his massive history of the Mediterranean with an epigraph by the sixteenth-century priest José de Acosta. “To this day,” wrote Acosta in his own equally massive Natural and Moral History of the East and West Indies, “they have not discovered at the Indies any mediterranian sea as in Europe, Asia and Affrike.”2 The irony is delicious in hindsight. While Europeans never found their own Mediterranean in the Americas, historians have since discovered the Atlantic as a unit of historical analysis. The very ocean that Acosta crossed to undertake missionary work in America has become an organizing principle through which scholars investigate the histories of the four landmasses it links. Yet the Atlantic does not have the coherence that Acosta first identified for the Mediterranean, nor that Braudel proposed and delineated centuries later; nor, indeed, is it possible to speak with confidence of an Atlantic system or a uniform region. Attempts to write a Braudelian Atlantic history—one that includes and connects the entire region—remain elusive, driven in part by methodological impediments, by the real disjunctions that characterized the Atlantic's historical and geographic components, by the disciplinary divisions that discourage historians from speaking to and writing for each other, and by the challenge of finding a vantage that is not rooted in any single place. But if a broad vision of the Atlantic such as the one Braudel sought for the Mediterranean is elusive, it nonetheless remains desirable. Scholars working in the field of Atlantic history have demonstrated the explanatory power of this geographic region as a unit of analysis: Atlantic perspectives deepen our understanding of transformations over a period of several centuries, cast old problems in an entirely new light, and illuminate connections hitherto obscured.