The Peace of Westphalia refers to a series of treaties signed in 1648 that ended the Thirty Years' War in Europe. This conflict involved many countries and was primarily fought over religious and political disputes. The treaties established a new framework for international relations, emphasizing the principles of state sovereignty and non-interference in the affairs of other states. The agreements resulted in significant territorial changes and recognized the independence of several states, including Switzerland and the Dutch Republic. The Peace of Westphalia is often considered a foundational moment in the development of the modern nation-state system and international law.