Gli strumenti del potere: per un’analisi della decima universale di papa Gregorio X nel Regno di Sicilia 1274-1280

This article aims to examine the main features of the sexennial tithe (1274-1280) of pope Gregory X to show how this form of taxation constituted one of the major manifestations of papal power in the late Middle Ages. In particular, the analysis will focus on five unpublished registers for the collection of the tithe in the collectorate formed by the ecclesiastical provinces of the Kingdom of Sicily. The first results of this research will allow to draw an initial picture of the action of the collector Pietro da Ferentino, to provide new and important details regarding the dioceses involved, the coins paid, the sums collected, and to shed new light on the dynamics of power and negotiation strategies between the various actors involved in the tithe.