With the end of the French wars, in the first half of the 19th century, the moral and spiritual authority of the papacy was strengthened, and a new trend, Ultramontanism, developed among Catholics who looked to Rome as the only center of Catholicism, who were unconditionally obedient to the Pope, and who looked to him for guidance on the new phenomena and problems of the changed world. But Rome was clearly in favor of the ancien régime, of restoration, of a social and political order based on the principle of authority, rejecting the bourgeois revolution and the new world that emerged from it, and its ideological basis, liberalism. In Belgium, a specific movement emerged that tried to reconcile Catholicism and liberalism, called Unionism. In my presentation, I would like to briefly introduce this Belgian model and its little-studied effects on the Hungarian Church.