In this article, I intend to highlight how the confessional question was not, in fact, the underlying cause of the Thirty Years War. On the contrary, religion became the perfect instrument to provide ideological coverage for the conflict and to bring together different wills in a world imbued with a strong religious feeling. In this regard, precise examples are collected that weaken the confessional vision of war. Finally, we propose an explanation of why this interpretation has had (and still has) so much predicament among different historians and historiographical visions.