by Emerich de Vattel
The Law of Nations deals largely with political philosophy and international relations, and has been said to have modernized the entire theory and practice of international law. The law of nations is the law of sovereigns; free and independent states are moral persons, whose rights and obligations we are to establish in this treatise.
Centuries after his death it was found that United States President George Washington had a number of overdue library books dating back over 221 years. One of them was The Law of Nations.