Final answer:
The Peace of Westphalia in 1648 recognized religious freedom, validating the concept of the sovereign nation-state, thus ending religious wars and recognizing the independence and sovereignty of entities that made up the Holy Roman Empire.
Step-by-step explanation:
In 1648, the Peace of Westphalia was a game-changer as it recognized the principle of religious freedom, thus validating the concept of sovereign nation-states across Europe. It served as a breakthrough in ending the destructive religious wars, such as the Thirty Years' War, that had been raging among Catholic and Protestant states since the Reformation. The treaty established the independence of numerous entities that composed the Holy Roman Empire and allowed rulers to decide on the official religion within their lands, thereby acknowledging the importance of national sovereignty and religious tolerance.
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