jats:titleAbstract</jats:title>jats:pHugo Grotius’s account of sovereign power injats:italicDe iure belli ac pacis</jats:italic>occupies a contested place in recent genealogies of modern sovereignty. This article takes a fresh approach by arguing that Grotius’s legal arguments do not do their work alone. They function within a broader horizon of what he calls “morals,” a field of reasoning that has debts to scholastic moral theology and Aristotelian moral science. Grotius's conception of sovereignty represents a modulation between law and “morals,” which allows him both to separate his scientific jurisprudence from the science of politics and nevertheless to reply to the political scientists on their own ground. The context of “morals,” however, is not narrowly political but inter-political, generating a potential tension between popular aspirations to sovereignty and the international order. Grotius’s “moral” handling of the issue offers an invitation to reflect on our current preoccupation with much the same concerns.</jats:p>