Hugo Grotius’s Dissertation on the Origin of the American Peoples and the Use of Comparative Methods en la lengua general de la Española decían batea por dornajo, y en Cataluña hay una villa que se llama Batea; luego de catalanes podemos decir que vinieron. (Bartolomé de Las Casas) Introduction Late in his life and while ambassador of Queen Christina of Sweden in Richelieu’s Paris, the Dutch scholar Hugo Grotius (1583–1643) published a short Latin treatise on the origins of the American Indians. There is little in what is known of Grotius’s other writings or his concerns at that time that easily explains why he was interested in that question, or why he would elaborate his argument the way he did. There is, however, a general context of early modern European cultural life in which Grotius’s treatise is clearly relevant, namely, the use of comparative methods in ethnological thinking. In this article I will attempt to explore this dimension, while at the same time offering some hypotheses concerning Grotius’s more immediate motivations. 1 Famous for his wide range of scholarly interests, encompassing in the typical fashion of a late humanist polymath religion, law, history and poetry, in the seventeenth century Grotius was best known for his theological and political writings, especially his rationalist Christian apologetics (from a liberal Protestant perspective), his irenic concern with the uniication of Christianity, and his contributions to the theory of natural law and natural rights. His participation in the Remonstrant controversy, his consequent interest in an Erastian model of relations between Church and State that would give civil magistrates control over ecclesiastical matters, and his rethinking of the natural law foundations for the theory of just war (including his arguments on free 1 I am grateful to Peter Borschberg, who has facilitated material for different aspects of this article, and to Anthony Grafton for his comments on this revised version.