 The School of Salamanca is a name for an intellectual movement or a certain group of theologians in sixteenth- and seventeenth-century Spain and Portugal. In a broad sense, it is more or less identical with Spanish Scholasticism, which also includes authors from the Spanish Netherlands. In a narrower sense, the School of Salamanca refers to two or three generations of pupils of Francisco de Vitoria, who was, in effect, the founding father of the school in both the broad and narrow sense. On the whole, it is more useful to choose the broader understanding of the term, even though it means considering some figures who were never at Salamanca; and this approach has been adopted here. Regarded as forefathers of the law of nations (ius gentium), they also were theoreticians willing to depart from the teachings of Aristotle, and some of them were early theorists of monetarist economics. They based themselves on the works of Thomas Aquinas but felt free to depart from them, especially in dealing with contemporary issues like Spanish expansion in the Indies and the challenge of Protestantism to Catholic Christianity.