Mexican War of Independence

The Mexican War of Independence was the eleven-year conflict, from 16 September 1810 to 27 September 1821, that ended Spanish rule over the mainland of New Spain and created an independent Mexico. Begun as a mass uprising led by a parish priest, it became a long guerrilla struggle and was finally won when royalist officers changed sides. Estimates of the total dead range from about 250,000 to 600,000.

In 1808 Napoleon forced the Spanish Bourbons to give up the throne and made his brother Joseph king of Spain. Across the Spanish Empire, local juntas claimed to rule in the name of the deposed Ferdinand VII, and in New Spain the crisis sharpened old tensions between American-born Spaniards, known as criollos, and officials born in Spain. Peninsular Spaniards in Mexico City overthrew a viceroy they considered too sympathetic to the criollos, and conspiracies spread among provincial elites.

One such group met in Querétaro. When it was discovered, the priest Miguel Hidalgo y Costilla called his parishioners to arms at Dolores on 16 September 1810, an appeal remembered as the Cry of Dolores. Tens of thousands of estate workers, miners and Indigenous villagers joined him, many armed only with farm tools, under a banner of the Virgin of Guadalupe. On 28 September they stormed the granary at Guanajuato where Spanish defenders had barricaded themselves, killing more than 500 people. At Monte de las Cruces on 30 October they defeated a royalist force near Mexico City but did not take the capital.

Royalist troops under Félix María Calleja then defeated the rebels at the Calderón Bridge. Hidalgo and other leaders fled north and were captured in Coahuila. Hidalgo was defrocked and executed on 30 July 1811.

The insurgency continued in the south under another priest, José María Morelos, who built a more disciplined army, took Acapulco and Oaxaca, and survived a 72-day siege at Cuautla. In 1813 he convened the Congress of Chilpancingo, which formally declared independence and set out the movement's aims, including the abolition of slavery and of caste distinctions. Royalist forces gradually regained the advantage, and Morelos was captured on 5 November 1815 and executed by firing squad in December.

For the next five years Vicente Guerrero kept up a guerrilla war in the southern hills, while neither side could win. The deadlock was broken by events in Spain. In 1820 a military revolt forced Ferdinand VII to restore the liberal Constitution of 1812, and many conservatives in New Spain began to see independence as a way to protect their own position.

The royalist commander Agustín de Iturbide opened talks with Guerrero, and on 24 February 1821 proclaimed the Plan of Iguala. It promised three guarantees: independence under a monarchy, the Catholic religion, and the union of all inhabitants, with citizenship regardless of European, African or Indigenous origin. Guerrero joined him, and their combined Army of the Three Guarantees won over most royalist units.

On 24 August 1821 the newly arrived Spanish envoy Juan O'Donojú signed the Treaty of Córdoba recognising independence. The army marched into Mexico City on 27 September, and independence was declared the next day. Spain rejected the treaty and did not recognise Mexico until 1836.

Iturbide was proclaimed emperor in May 1822, but he was forced to abdicate in 1823 and a federal republic was established, set out in the Constitution of 1824. Mexico celebrates its independence on 16 September, the anniversary of Hidalgo's call to arms.

Our 1815 map shows the Viceroyalty of New Spain in the middle of the war, and our 1878 map shows independent Mexico after the losses of territory that followed independence.