In Italy, the death of the Duke of Mantua and Montferrat without near heirs had given rise to war. The next heir was a very distant relation, the Duke of Nevers, whose family had long been naturalized in France. To Spain the presence of a dependent of France so near her possessions in the Milanese was in the highest degree undesirable, and she called upon Ferdinand to sequester the territory till another way of disposing it could be found. If in Germany before Ferdinand's election the rights of the Emperors had been but a shadow, those which they possessed in the old kingdom of Italy were but the shadow of a shade. But whatever they were, Ferdinand was the man to put them forth, and whilst Richelieu was engaged at Rochelle, Spanish troops had overrun Mantua, and in conjunction with the Duke of Savoy, ready now to seek his own interests by fighting for Spain, as in earlier days to seek his own interests by fighting against her, were besieging the Duke of Nevers in Casale, the only fortress which remained to him. [Sidenote: § 3. Italian feeling against the Emperor.] This intervention of the Spaniards in the Emperor's name caused even greater indignation in Italy than their intervention in the Palatinate had caused in Germany. For in Germany the Emperor's name was in 1621 still connected with the ideas of law and order. In Italy it reminded men of nothing but foreign domination, a memory which was none the less vivid when the Emperor used his authority, whatever it might be, to support the real foreign domination of the immediate present, the Spanish domination in Milan. The Italian princes took alarm. Venice and the pope summoned France to their aid, and in March, 1629, Richelieu, taking Lewis with him across the snowy passes of the Alps, reduced the Duke of Savoy to submission, and forced the Spaniards to raise the siege of Casale. [Sidenote: § 4. Check inflicted on him by Richelieu.] Casale was the Stralsund of Italy. A power which had ventured to clothe itself in the attributes of a national authority, with even less reason than in Germany, had found its limits. Richelieu had the general feeling on his side. [Sidenote: § 5. The last Huguenot rebellion.] He did not venture to do more in Italy. The Duke of Rohan, the brother of that Soubise who had begun the war of Rochelle in 1625, had roused the Huguenots of Languedoc and the Cevennes to a fresh attempt at resistance, half Protestant, half aristocratic. As if the Rochellese had not sufficiently suffered for the mistake of calling in foreign aid, Rohan followed their example, and was foolish enough to ask for help from Spain. But the Spanish troops came not to his aid. Richelieu hurried back from Italy, made peace with England, and pitilessly crushed the rebellion in the south. Once more the victory was attended by the confirmation of the religious liberties of the Huguenots. They might worship as they pleased, but political independence they were not to have.