The power affirmed by Ferdinand III was taken away from him and returned to the rulers of the imperial states. The leaders of the imperial states could now choose their own official religions. Catholics and Protestants were defined as equal before the law, and Calvinism was recognized as an official religion.   The independence of the Dutch Republic, which practiced religious tolerance, also provided a safe haven for European Jews.  The negotiations lasted five years. That is partly because it was unprecedented. These negotiations had never taken place. It was a peace congress for the whole of Europe to build a pax generalis, a general peace. The diplomatic ceremony and the etiquette, for example, the question of who prevailed over who entered a room were symbolic things that this era took very seriously.
The first six months were spent arguing about who should sit where and who should go to a room before that. The main French and Spanish emissaries never managed to meet because it was not possible to agree on the right protocol. A special postal system processed letters between the envoys and their sponsors at a time when it took ten days or more to send a message from Munster to Paris or Vienna and twenty days or more to Stockholm or Madrid. Deals were slowly hammered. It took nearly three weeks for the signing ceremony, which began on the afternoon of Saturday, October 24, 1648, at 2 p.m. The war became less about religion than a continuation of the rivalry between France and the Habsburgs for the political domination of Europe. Sweden, a great military power of the time, intervened in 1630 under the great General Gustavus Adolphus and began the Great War on the continent. Spain, which finally wanted to destroy the Dutch rebels in the Netherlands and the Dutch Republic, intervened under the pretext of helping its dynastic ally of the Habsburgs, Austria. Catholic France, which could no longer tolerate the encirclement of two great Habsburg powers on its borders, entered the coalition on the Protestant side to confront the Habsburgs.
Negotiations took place in Munster between the Holy Roman Empire and France, as well as between the Dutch Republic and Spain, which signed on 30 January 1648 a peace treaty which was not part of the peace of Westphalia.  Munster had been a purely denominational community since his recruit in 1535. It housed the chapter of the archdiocese of Munster. Only Roman Catholic religious freedom was permitted, while Calvinism and Lutheranism were forbidden. However, it is essential that this conference was not led by a generally recognized authority. It was not ruled by the Holy Roman Emperor. After all, he was one of the belligerents. These negotiations were also not conducted by the Pope, because the Pope refused to recognize the agreements with the Protestants who, in turn, rejected his claims of authority.
The peace conference to end the war opened in December 1644 in Munster and Osnabruck. There were no less than 194 states, from the largest to the smallest, represented by 179 plenipotentiaries.