What led to the series of treaties called the Peace of Westphalia?

In his essay on tolerance, Yonatan Zunger tells us that tolerance is not a moral precept and neither is it a moral absolute. He says in fact, that it is a social norm because it allows people to live side by side without being at each other's throats.

Then he goes on to show us how the Peace of Westphalia - a series of treaties - brought peace to war that had carried on for almost 6 generations between 1524 and 1648 and saw tens of millions of deaths on both sides between the Roman Catholic and the Protestants in Europe.

The Peace of Westphalia was built in fact on two radical tenets: that each ruler had the right to choose the religion of his state and that Christians living in those principalities where their faith was not the established faith, still had the right to practice their own religion.

This was a decision in essence to accept the risk of the monster rather than the reality of war.

It was the political foundation for the concept of secularism: that religious matters are so uncertain that they were actually beyond the powers of the state to mandate.