The Papal States, States of the Church, States of the Pope, States of Saint Peter or the Republic of Saint Peter [ref. necessary] are the States which were between 754 and 1870 under the temporal authority of the pope. The first nucleus of these States was called Heritage of Saint Peter. The Lateran Accords in 1929 having settled the Roman question without however pronouncing on the abolition of the Papal States proclaimed by Victor-Emmanuel II in 1870 but not accepted by the Pope, it is considered that their continuity is found today in the Vatican City State.
If in 344 was completed the basilica of Saint Peter in Rome, it appears that the Byzantine Empire seized the rich religious city from 593 under Pope Saint Gregory the Great, and it was not until 756 that the King of the Franks Pepin the Short frees Rome, conferring on Pope Stephen II power over the regions contiguous to Saint Peter's Basilica, giving rise to the States of the Church, which have become the Vatican State.
The origin of the Papal States goes back to the donation of Pépin. By this text promulgated in 754 before the assembly of Quierzy, Pepin the Short, indebted to Pope Zacharias for having legitimized the overthrow of the Merovingians, undertakes to cede to Stephen II - successor of Zacharias in 752 - a territory to be conquered on the Lombards and corresponding to the ancient exarchate of Ravenna. These are essentially poor lands (including in particular the Pontine marshes), where agriculture has been practiced for centuries. The donation was confirmed in 774, in Rome, by Charlemagne, son of Pepin.
A forgery called the Donation of Constantine was later used to bolster the legitimacy of the Papal States. According to this document composed in the 8th or 9th century and integrated into the pseudo-Isodorian Decretals, the Emperor Constantine I would have ceded in 335 all the provinces of the West to Pope Sylvester I. The document purports to reproduce a letter from Constantine to Sylvester in which the emperor shares temporal sovereignty over Rome and Italy with the bishop of Rome and confers on the latter spiritual primacy over all the ecclesiastical patriarchates. The Donation is used, for example, by Pope Adrian I to have Charlemagne recognize the prerogatives of the Roman bishop over certain towns. The authority of the Donation, recognized even by opponents of the papacy, thus legally founded the temporal power of the pope throughout the Middle Ages before the falsification was unmasked in the 16th century by Laurent Valla. It was nevertheless necessary to wait for the Renaissance for the critics to definitively rule out the Donation.
From the Middle Ages to modern times
These States increased in 1115 by the inheritance of the countess Mathilde of Tuscany.
In response to the fratricidal struggles between Guelphs (supporters of the Pope) and Ghibellines (supporters of the Emperor), the Peace of Venice of 1177 consecrates the independence of the Papal States vis-à-vis the Holy Empire.
In the middle of the fourteenth century, the Trecento, the Papal States were at their maximum extension and the Aegis Constitutions established in 1357 seven provinces in the central whole of Italy: Rome, the provinces of Countryside and Maritime (between Rome, Ostia, Liri Valley and Terracina), the heritage of Saint Peter in Tuscany, Sabina, the march of Ancona and the Duchy of Spoleto; to which must be added the enclaves of Bénévent and Pontecorvo in the kingdom of Naples, Avignon and the Comtat Venaissin.
During the Italian wars, Pope Julius II took possession of the cities Caesar Borgia had conquered in Romagna and the Marches. Leo X adds the towns of Emilia which are Piacenza, Parma, Reggio, Modena and Bologna. The duchy of Parma and Piacenza was however detached in 1545 by Pope Paul III in favor of the Farnese house, to which