"The Rights of War and Peace" by Hugo Grotius is a treatise published in 1625 that established foundational principles of international law. Writing during the Thirty Years' War, Grotius sought to create a rational legal framework governing warfare and relations between nations, based on natural law, reason, and shared customs. He argued that universal principles of justice could regulate state behavior even without a higher authority, distinguishing just causes for war from lawful conduct during conflict. His work profoundly influenced modern international law and continues shaping debates on state sovereignty and just war theory. (This is an automatically generated summary.)
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