This work is a translation of de Raynevals 1803 classic The Institutions of Natural Law and the Law of Nations. Having been translated into Spanish shortly after its appearance, The Institutions was the reference point of international law for much of the French- and Spanish-speaking world during the Nineteenth Century. As a result, arguably, it is the single most important text of international law to appear between the 1814 Congress of Vienna and the 1919 Treaty of Versailles. This, the first ever English translation of de Raynevals The Institutions, provides the English-language world with the last text conceived of, and written, during the era of bilaterial, European, Law of Nations; before the waltz into the Concert of Europe and the growth of multilateral diplomacy, with its end point todays United Nations. De Rayneval is a product of the Ancien Regime who turned to writing The Institutions after having been purged from the Quai dOrsay by the French Revolution. It may be said that in brokering the 1782 Peace of Paris which saw the United Kingdom recognise the United States of America, that Rayneval ended the war which his brother started; as it was Conrad-Alexandre de Rayneval who was the architect of the previous French policy of supporting, and later recognising, the American insurgence of the Thirteen Colonies. Through his faithful translation and introductory essay, Jean Allain makes this classic work accessible to the new audience of the English-language World.