Mare Liberum vs. Mare Clausum : Grotius, Freitas, and Selden's Debate on Dominion over the Seas

Sixteen years after the publication of Grotius’s Mare Liberum (1609), Serafim de Freitas, a Portuguese friar, published a reply to Grotius’s attack upon the foundations of the Iberian overseas empire.  Freitas’s vindication of the Portuguese dominion over the high seas has, however, been consigned to obscurity, as the Anglophone literature concentrated on John Selden’s Mare Clausum (1636).  This neglect is unjustified.  Not only is Freitas’s treatise an earlier and more systematic response to Grotius, but it also anticipates many of the arguments later deployed by Selden.  The purpose of this article is thus to rescue Freitas’s arguments from oblivion.