The Thirty Years' War was a devastating conflict fought primarily in Central Europe.

It began as a religious conflict between Protestant and Catholic states within the Holy Roman Empire.

The war was triggered by the 'Defenestration of Prague' in 1618, where Protestant nobles threw Catholic officials out of a castle window.

The conflict evolved from a religious war into a wider political struggle for the balance of power in Europe.

Major European powers, including Sweden and France, intervened in the war to counter the power of the Catholic Habsburg dynasty.

The war was characterized by its extreme brutality and the widespread use of mercenary armies.

These armies devastated the German lands, leading to massive population loss from fighting, famine, and disease.

The Peace of Westphalia, a series of treaties signed in 1648, finally ended the war.

The peace settlement recognized Calvinism alongside Catholicism and Lutheranism and expanded the religious autonomy of German princes.

The Thirty Years' War is considered one of the most destructive conflicts in European history, and the Peace of Westphalia established the modern concept of state sovereignty.