The Thirty Years' War, which began with the Bohemian Revolt in 1618, had ravaged Europe and particularly the Holy Roman Empire. The complex web of religious, dynastic, and territorial disputes had taken the lives of up to eight million people due to battles, food shortages, and disease. The devastating conflict was finally brought to an end with the Peace of Westphalia.
The complexities of the war were reflected in the peace negotiations. 109 delegations from the Holy Roman Empire, France, Sweden, and their respective allies were involved in the discussions that resulted in two separate treaties. These took place in the neighbouring cities of Münster, which was strictly Catholic, and Osnabrück, which was controlled by a Lutheran council because each side wanted to meet on territory under its own control.
The two treaties that formed the Peace of Westphalia confirmed the autonomy of states with the Holy Roman Empire and ensured religious tolerance by allowing rulers to choose their own religion, while their subjects were not forced to follow this. The treaties also redefined the borders and sovereignty of numerous European states, while Spain separately recognized the independence of the Dutch Republic.
The treaties were denounced by Pope Innocent X as "null, void, invalid, iniquitous, unjust, damnable, reprobate, inane, empty of meaning and effect for all time". Nevertheless the Peace of Westphalia introduced a more secular understanding of state sovereignty, laying the foundation for modern international relations.
