The Peace of Westphalia, signed in 1648, marked the conclusion of the Thirty Years' War and is often credited with establishing the framework for modern nation-states. This treaty recognized the sovereignty of a number of states within Europe, including the principle of non-interference in the internal affairs of these states. The outcomes of the treaty helped to shift the focus from dynastic rule to state sovereignty, laying the groundwork for modern international relations. By affirming the importance of territorial boundaries and state governance, the Peace of Westphalia encouraged diplomatic negotiations and set a precedent for future treaties, shaping Western political thought.