Part of the aftermath of the Protestant Reformation was a series of wars that attempted to abolish Protestantism and restore the Catholic Church’s predominance. The most vicious of these was the Thirty Years War (1608-1648)’ fought mainly in Germany. While religious issues were the direct cause of the conflict, it evolved into a larger political struggle in which France and Sweden sought to reduce the strength of the Habsburg dynasty that ruled Austria. Eventually most of Europe was involved and Austria was forced into peace, while France and her allies threatened to take Prague, Munich, and Vienna.
Modern estimates are that the population of Germany declined by 20% during the Thirty Years War, in some regions the decline was 50% as entire villages disappeared. Long-term effects of the war were the establishment of Switzerland and the Dutch Republic, the emergence of France as the dominant land power of Europe, and the continued fractionalization of Germany that long delayed its unification into a state.