Mexican War of Independence the Congress of Chilpancingo, which gave the insurgency its own legal framework. After the defeat of Morelos, the movement survived as a guerrilla war under the leadership of Vicente Guerrero. By 1820, the few rebel groups survived most notably in the Sierra Madre del Sur and Veracruz. The reinstatement of the liberal Constitution of Cadiz in 1820 caused a change of mind among the elite groups who had supported Spanish rule. Monarchist Creoles affected by the constitution decided to support the independence of New Spain; they sought an alliance with the former insurgent resistance. Agustín de Iturbide led the military
Mexican War of Independence of Iguala, Iturbide persuaded Guerrero to join his forces in support of this conservative independence movement. A new army, the Army of the Three Guarantees, was placed under Iturbide's command to enforce the Plan of Iguala. The plan was so broadly based that it pleased both patriots and loyalists. The goal of independence and the protection of Roman Catholicism brought together all factions. Iturbide's army was joined by rebel forces from all over Mexico. When the rebels' victory became certain, the Viceroy resigned. On August 24, 1821, representatives of the Spanish crown and Iturbide signed the Treaty of Córdoba, which