Spanish attempts to reconquer Mexico
Mexican independence was officially achieved on September 27, 1821, under the Treaty of Córdoba. Spain did not recognize the treaties, arguing that the viceroy Juan O'Donojú had no authority to recognize the independence of any overseas province. This situation was dangerous to the newly acquired independent status of the nation, which had not yet been recognized by any of the European powers that could support it, and the threat of Spanish reconquest was a constant worry to the leaders of the nascent regime. On May 13, 1822 decrees were issued by the government to imprison anyone who conspired against Mexico's independence.
Economic history of Mexico
In 1820, Spanish liberals staged a coup and forced Ferdinand to reinstate the Spanish Constitution of 1812 passed by the Cortes de Cadiz. For elites in New Spain, the specter of liberal policies that would have a deleterious impact on their social and economic position propelled former royalists to join the insurgent cause, thus bringing about Mexican independence in 1821. A pact between former royalist officer Agustín de Iturbide and insurgent Vicente Guerrero unified under the Plan de Iguala and the Army of the Three Guarantees brought about Mexican independence in September 1821. Rather than the insurgency being a social revolution, in the end it allowed conservative forces in now independent Mexico to remain at the top of the social and economic system.