The Thirty Years War ended with which treaty?

The story behind the answer

The Thirty Years’ War (1618–1648), a devastating religious and political conflict across Central Europe, ended with the Peace of Westphalia in 1648—a series of treaties signed in Münster and Osnabrück. Not to be confused with the Peace of Prague (1635), which was a mid-war settlement, nor the Treaty of Paris (1783, ending the American Revolution) or the Treaty of Versailles (1919, after World War I).

Westphalia is famous for shaping the modern state system: it affirmed state sovereignty and non-interference, broadened religious settlement (recognizing Calvinism alongside Lutheranism and Catholicism), and acknowledged the independence of the Dutch Republic and the Swiss Confederation. Memory tip: W for War’s end—Westphalia—locks in the West’s idea of sovereign states in 1648.