The essays in this book cover a fast-paced 150 years of Vatican diplomacy, starting from the fall of the Papal States in 1870 to the present day. They trace the transformation of the Vatican from a state like any other to an entity uniquely providing spiritual and moral sustenance in world affairs. In particular, the book details the Holy See’s use of neutrality as a tool and the principal statecraft in its diplomatic portmanteau. This concept of “permanent neutrality,” as codified in the Lateran Treaties of 1929, is a central concept adding to the Vatican's uniqueness and, as a result,...