Hugo Grotius 
Rights of War and Peace [PDF ebook] 
Including the Law of Nature and of Nations

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. It is historically accurate to say, that, until formulated by Grotius, Europe possessed no system of international law. Others had preceded him in touching upon certain aspects of the rights and duties of nations, but none had produced a system comparable to his.