The fate of the Papal States during the unification of Italy is of particular scientific interest. Despite the economic backwardness of the state, which was aggravated during the years of the Restoration, the papacy sought to maintain its influence in Italian and European politics. The traditions of the theocratic state management absorbed much from the practice of governing the Catholic Church, which led to the formation of a special political culture. Due to this, the political practice of the Papal States in the first half of the 19th century combined extremely retrograde elements and ideological innovation in an original way, which made it possible to use the potential of the Catholic doctrine and maintain a leading political role in the Appenines. The early 1840s saw the crystallization of the doctrine of neo-Guelphism, which believed that the papacy was destined for a special mission in the political revival and unification of Italy. This doctrine evoked a wide response throughout the entire Apennines and beyond. The purpose of this article is to analyse the political and administrative practices of the papacy, the uniqueness of its political culture and social climate. The Papal States are characterized by a complex combination of secular and ecclesiastical methods of influencing society. Ideas about the political role of the papal state and its immediate prospects were often formed not so much around its objective potential as by centuries-old belief in the fundamental differences between the nature of this state and the nature of its Italian neighbours. The innovative course taken by the newly elected Pope Pius IX in 1846–1847 seriously undermined this conviction, but did not alienate the model of the political evolution of the Papal States from the fate of some other Italian states. Identification of the features of the political culture of the Papal States is possible only by studying a range of specific sources. The article deals with the basic official, religious and secular, documents of the Curia, and the evidence left by the publicist and fictional literature of the era. The results of the study will allow a better understanding of the condition of the papal state on the eve of the 1848 revolution, as well as the reasons for the subsequent conservative turn.