Mexico wins independence

On September 27, 1821, the Trigarante army, led by Agustin de Iturbide, marched into Mexico City, and the next day Mexico declared its independence. Spanish rule that began with the conquest of Tenochtitlan in 1521 was over. Just a month earlier, on August 24, the new Spanish representative Juan O'Donoju had signed the Treaty of Cordoba, recognizing independence under a constitutional monarchy. Spain's government refused to ratify it, and only recognized Mexico in 1836.¹²

After Hidalgo and Morelos were executed, the insurgency shrank to guerrilla bands under Vicente Guerrero and others. The turning point came in Spain: a liberal revolution in 1820 restored the constitution of 1812, alarming Mexican conservatives, the Church and army officers who feared reforms. Iturbide, a royalist officer, switched sides. In February 1821 he issued the Plan of Iguala, with three guarantees: the Catholic religion, independence, and union of Spaniards and Americans. This offer drew royalists and insurgents together, and Guerrero joined him.¹²

The new country was enormous, reaching from Central America to California and Texas. Iturbide had himself crowned Emperor Agustin I in 1822, but generals led by Santa Anna overthrew him in 1823, and in 1824 Mexico adopted a federal republican constitution. Independence did not remove deep inequalities: the guarantee of equality did not end the caste hierarchy overnight, though slavery was abolished in stages from 1829. The decades that followed brought instability, the loss of Texas and war with the United States.²