Why were bloody religious wars so incredibly frequent in Europe in the century following the Reformation?

Question

Beginning in 1520, right after Martin Luther's Reformation, bloody religious wars began that kept recurring almost yearly for over a century. The Reformation's rapid spread drew battle lines accross Europe as Catholic armies were fielded to crush the Protestants into submission, engulfing the continent in intermittent war from the 1520s to the 1640s. But what was the real cause of these _recurring_ wars? In other words, "Why not live and let live?"

Answer 1

The simplest reason is that changing the religion threatened the balance of power in the countries, especially when certain noble and royal families relied upon the support of the church for their sense of authority. The support of the Catholic church was something that helped them to rationalize their place in the world and to stay in power. Consider, for example, the "divine right" of kings and the concept of a hierarchy handed down from heaven. Many noble families saw these concepts as acceptable and wanted to maintain them. Equally, other powerful families saw Calvinism and other branches of Protestantism as a road to power and a way to disrupt the authority of the Catholic church and their enemies, so they converted in the hopes of getting around the status quo and finding a new advantage for themselves. All of that behind the scenes planning turned into mobs, riots, destruction of churches, defacing statues, and battles where the peasants were the ones who suffered the most.