Answer:
The war had initially started due to the fact that Holy Roman Emperor Ferdinand II of the House of Habsburg closed many Protestant churches in Bohemia. He also forced Protestants to convert to Catholicism. This had been a violation against the Peace of Augsburg and caused many religious tensions to increase. The act that demonstrated a refusal to cooperate was in 1618 when the Protestant Bohemia nobility had protested the violation. They rejected Ferdinand II's rule by throwing his representatives out of one of the windows in the Prague Castle. The events mentioned above were the beginning of a revolt by the Bohemian states as well as the onset that is the Thirty Years' War.
Explanation:
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