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a liberal Catholic movement in Italy in the first half of the 19th century, during the Risorgimento, that adopted the medieval Guelphs’ idea of the pope as the defender of Italy. Before 1843 it was a literary movement that called for linking up Catholicism with progress and freedom. In 1843, with the appearance of V. Gioberti’s On the Moral and Civil Primacy of the Italians, it acquired a political nature and a political program—an appeal for the alliance of the national liberation movement with the Catholic Church and clergy and for the creation of a federation of Italian states headed by the pope.
When the “liberal” Pius IX ascended the papal throne in 1846, the Neo-Guelphs rallied around him. The movement gained adherents not only among the Catholic clergy, liberal nobility, and bourgeoisie but also among the broad strata of the people. During the Italian Revolution of 1848–49, after Pius IX on Apr. 29, 1848, publicly came out against the newly begun national liberation war with Austria and then openly sided with the counterrevolutionary camp, the myth of the pope’s liberalism and his patriotism was shattered. Neo-Guelphism lost its political strength.