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.
Republic of the Rio Grande
After a decade of strife, Mexico won its independence from the Kingdom of Spain in 1821. After a failed attempt at a monarchy, Mexico adopted a new constitution, the 1824 Constitution. This new constitution established los "Estados Unidos Mexicanos", or "the United Mexican States," as a federal republic. During the war for independence, many rebels were driven to Coahuila and Nuevo León, where this revolutionary mentality won the hearts and minds of the people.