-With backing from Spain, Poland, and other Catholic states, Ferdinand attempted to begin reformation by force again
-When Ferdinand became emperor, the Bohemians rebelled and were later defeated by him
-After Ferdinand defeated the Bohemians and their Protestant allies, Protestant powers like the Netherlands and Sweden sent out troops into Germany
-Soon, political motives overruled religious issues, leading to states of different religions to join together in alliance to suit their own interests
-At one point Catholic France Joined Lutheran Sweden against the Catholic Hapsburgs
-Mercenaries, or soldiers for hire, burned villages, destroyed crops, and killed without mercy
-Murder, torture, famine and disease led to depopulation, or reduction in population
-Historians estimate that as many as 1/3 of the people in the German stats may have died in result of the war
-Finally, in 1648, the exhausted combatants accepted a series of treaties, known as the Peace of Westphalia
-The treaties aimed to bring about a general European peace and to settle other international problems

In Summary...