The Private as a Core Part of International Law: The School of Salamanca, Slavery, and Marriage (Sixteenth Century)

In "Gender and the Lost Private Side of International Law," Karen Knop argued that "recuperating private international law as a lost side of international law can open up counter-disciplinary research on gender in the history of international law."1 In this essay, I use Knop's argument to revisit our understanding of the sixteen century "School of Salamanca"2 and its importance for international legal history from a gender perspective. I focus on the practice of jurists and theologians associated with the School of Salamanca in assessing the validity of marriages of newly converted Indigenous peoples in Brazil (negros da terra), and later the validity of remarriages of Indigenous people and enslaved Africans (negros da Guine) who had already been married in places from which they had been forcibly removed.3 To do this, these jurists and theologians engaged in private international law (or conflict of laws) reasoning. A key question involved determining what law governed each marriage-was it ius gentium, natural law, or canon law? Examining their arguments, I argue, offers an instance of Knop's insight that recuperating private international law allows us to redress the invisibility of women in the history of international law. In my case study, not only do we better understand "how power operates through international legal concepts and institutions"4 in the private sphere of the family in the colonies, but also, and crucially, how "private international law make[s] visible the effects of colonial . . . law on gender relations and national identity at home,"5 to borrow Knop's words.