Treaty of Westphalia/Peace of Münster (1648).

In 1648, three major peace treaties were concluded, the first between Spain and the Dutch Republic (January 30), and then the second and third treaties, agreed later in the year on the same day (October 24), involving the Holy Roman Empire, France, and Sweden. Collectively, the treaties brought to a negotiated settlement the Thirty Years' War that had begun in 1618. Their legacy in the history of international relations has been enormous: the Westphalian Peace of 1648 has come to represent a paradigm shift in the definition of the “state” and of interstate relations. Whether this view is justifiable, though, is a matter of debate