How did religious differences lead to conflicts in europe during the sixteenth and seventeenth centuries?

The conflicts began with the minor Knights' Revolt (1522), followed by the larger German Peasants' War (1524–1525) in the Holy Roman Empire. Warfare intensified after the Catholic Church began the Counter-Reformation in 1545 against the growth of Protestantism. The conflicts culminated in the Thirty Years' War (1618–1648), which devastated Germany and killed one-third of its population. The Peace of Westphalia (1648) put an end to the war by recognising three separate Christian traditions in the Holy Roman Empire: Roman Catholicism, Lutheranism, and Calvinism. Although many European leaders were 'sickened' by the bloodshed by 1648, religious wars continued to be waged in the post-Westphalian period until the 1710s, and collective memory of the wars lasted even longer.
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