The first scene of religious conflict after the Crusades was Western and Central Europe during Reformation.
Religious conflicts have been happening long before the clear lines appeared between the Catholics, Protestants, or Orthodox. Still, as time went by the brutality of religious wars also increased.
Protestant Reformation that started with the publication of Martin Luther’s “95 theses” (1517), spurred another series of conflicts in Europe. Those conflicts lasted for more than 130 years and ended in 1648 with the Treaty of Westphalia, also considered to be the first step towards the formation of a system of international relations, existing today. Ideas to purify the church and to get rid of the bureaucratic elements that have become part of it and have corrupted it as an institution of faith were of crucial importance. Luther and his followers believed that the Bible was the only legitimate spiritual source and that the path to self-purification lay in honest work and simplicity.
The movement diversified very fast and spread from Germany to Switzerland where H. Zwingli and J. Calvin led it. The invention of the printing press pushed Reformation to propagate to England, France, Scotland, and, later on, Central Europe, turning most of continental Europe into the realm of religious wars. The attempts of the Holy Roman Church to save itself and remain the ruling authority was doomed to failure, as no half measures could satisfy supporters of religious freedom. So, the most significant religious wars in Europe ended only with the signing of a Treaty that established freedom of faith and thus put an end to wars based on religion for a long time.