In this authoritative work, Emmanuelle Jouannet, a leading French scholar of public international law and legal theory takes a fresh look at the emergence of classical international law and provides an original and decisive reinterpretation. According to the modern and conventional account, Grotius, and his predecessors the Spanish jurists, are credited as the 'fathers' of the modern ius gentium. But this picture of history is now both inaccurate and incomplete. With rare erudition based on an exhaustive analysis of the foundational concepts and principal texts of the great jurists of the period, Jouannet shows that it was only during the 18th century Enlightenment that a genuine doctrine of international law emerged. In particular Jouannet focuses on the work of a Swiss jurist Emerich de Vattel (1714-1767), for long a forgotten figure, showing how his ideas engendered fresh understanding of what international law meant, and stimulated the fundamental debates that international lawyers are still engaged in today. The translation has been prepared under the supervision of Robert Howse, professor of international law at NYU Law School, and the author herself.