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.
Mission Indians
When Mexico gained its independence in 1834, it assumed control of the Californian missions from the Franciscans, but abuse persisted. Mexico secularized the missions and transferred or sold the lands to other non-Native administrators or owners. Many of the Mission Indians worked on the newly established ranchos with little improvement in their living conditions.