At the Congress of Vienna, Cardinal Ercole Consalvi, secretary of state to Pope Pius VII, amazed the world with his diplomatic prowess as he asserted the moral authority of the papacy against the armies and victories of the allied powers. While stressing the degradation and spoliation suffered by the Pope at the hands of Napoleon, he exploited the various participants' fears of imbalance on the Italian peninsula to defeat all contenders for control of the Legations. From a position of extreme weakness he had given lie to the early warnings of Lebzeltern, the Austrian ambassador in Rome, who had assured the Pope that he would never recover the northern provinces. By June, 1815, the diplomats in Vienna had agreed to reestablish, with only minor modifications, the Papal States as they had existed before Napoleon's armies had scrambled their borders. The Austrian provisional government therefore transferred the Legations to the Pope's authorities in July of that year. Having won the day diplomatically, Consalvi now faced the consequences of his hard-fought victory and turned his talents to the integration of the contested areas with those previously recovered, a prodigious task complicated by the administrative disparities separating the regions.

On one hand, the Legations and the Marches had experienced French rule for some eighteen years, and the Austrian provisional government had little altered the changes wrought after 1796.