Since the nineteenth century, Hugo Grotiuss ‘Rights of War and Peace’ has commonly been seen as the classic work in modern public international law, laying the foundation for a universal code of law. However, in the seventeenth century and during the Enlightenment, the work was considered a major work of political theory that strongly defended the rights of individual agents – states as well as private persons – to use their power to secure themselves and their property. Grotiuss continuing influence owed much to the eighteenth-century French editor Jean Barbeyrac, whose extensive commentary was standard in most editions, including the classic, anonymously translated, English one (1738), which is the basis for the Liberty Fund edition. The present edition also includes the Prolegomena to the first edition of ‘Rights of War and Peace’ (1625); this document has never before been translated into English and adds new dimensions to the great work.