The Author studies the fundamental problem of Roman Curia in making peace with the Protestants and of Catholic Church in accepting the extensive loss of part of Europe. He focuses on the analysis of the content, motivations and objectives in publishing the Pope Innocent X?s breve Zelo domus Dei where the Pope in the name of the Church refuses to accept the outcome of the Westphalia negotiations.
For the representatives of the Church, the possibility to make peace with protestant ?heretics? was a compelling doctrinal and moral problem. The study deals with the fact that the formal refusal of the peace treaty by the Holy See had some relevant ecclesiastical and political consequences.