At the Congress of Verona, Metternich once more won the day. With this backing, the French envoys, Montmorency and Chateaubriand, in defiance of their home instructions, committed France to war with Spain. An agreement was reached that, in default of radical changes in the Spanish Constitution, France and her allies would resort to intervention. On the part of England, Wellington rejected this proposal, but all the other powers consented. When the French Ambassadors returned to France, their Prime Minister, Villèle, vented his dissatisfaction by repudiating his envoys. He addressed himself to the foreign Ambassadors at Paris with a request that the allies' demands on Spain be postponed. Montmorency at once resigned. No notice was taken of Villèle's request except by England. The King himself went over to the war party and appointed Chateaubriand his Minister of Foreign Affairs. Great Britain's tentative offer of mediation was summarily rejected by France. To Villèle, King Louis XVIII. thus explained his attitude: "Louis XIV. destroyed the Pyrenees; I shall not allow them to be raised again. He placed my house on the throne of Spain; I shall not allow it to fall."
The Spanish Government was resolved to maintain the national independence of Spain. It would make no concession. The French Ambassador in Madrid was recalled. At the opening of the French Chambers in January, the King himself announced his decision: "I have ordered the recall of my Minister. One hundred thousand Frenchmen, commanded by a prince of my family, whom I fondly call my son, are ready to march with a prayer to the God of St. Louis that they may preserve the throne of Spain to the grandson of Henri IV. They shall save that fair kingdom from ruin and reconcile it to Europe." By the middle of March, the Duke of Angoulême and his staff left Paris. On April 7, the French vanguard crossed the Bidassoa, and the Duke entered Irun, welcomed by Spanish royalists. About the same time the Cortes and Constitutional Ministry left Madrid, and compelled King Ferdinand VII. to accompany them to Seville. The forces of the Spanish Government fell back without striking a blow. Bands of freebooters calling themselves royalists went pillaging throughout the northern provinces. The commandant of Madrid felt constrained to beg the French to hasten their advance lest the city fall a prey to the freebooters. Already the looting of the suburbs had begun, when the French entered the Spanish capital on the 24th of May. A regency was appointed under the Duke of Infantado. The Continental powers sent accredited representatives to Madrid. Meanwhile the Cortes withdrew to Cadiz. King Ferdinand refused to accompany them; so they suspended his powers and appointed a regency over his head. The French prepared to lay siege to Cadiz.