Mexico's inability to establish permanent central control over its territories was a critical factor in the war with the United States. Mexico exercised less supervision over its states and territories than had Spain, which had improved its command over the borderlands during the eighteenth century. After Mexican independence in 1821, federalism appealed to regions along the northern and southern periphery out of a desire for free trade and self-rule. Frontier states and territories had been accustomed to receiving assistance in fighting Indians, which was not forthcoming from the central government after independence. The absence of economic integration and decent roads as well as the neglect of colonization projects led to an eventual lapse of allegiance to the national government. The loss of Texas in 1836 was a resounding blow to Mexico City. The question as to when Texas would be annexed to the United States in part determined the outbreak of hostilities between Mexico and the United States. California enjoyed a tranquil autonomy while New Mexico became sullen and divided. Merchants in northern and coastal regions profited from free trade rather than the protectionism demanded by Mexico City. Smuggling made Monterrey and Pacific ports into lucrative commercial areas. In Yucatán, the elites revolted and sought outright independence from Mexico. Constant revolts in the north and southeast would divert scarce funds, resources, and manpower from the effort to prepare for war against the U.S. invaders. This discord also meant that states and territories along the periphery would not provide resources to the central government for the war effort.
In California, the key event was secularization of the missions in 1834. This created a large class of California rancher-farmers eager to trade hides and tallow and led to a class structure less rigid than that in Mexico. Rancho life and strong family values dominated California society. Increasingly close commercial ties to U.S. ports meant that U.S. settlers were not forced to accept the Catholic religion or to pay taxes. California found that its trade depended on the sea rather than on overland trade with New Mexico or through Sonora. The only alternative was trade with U.S. and British merchants.
New Mexicans, on the other hand, were predominantly of Spanish ancestry rather than Mexican and carried on active overland trade with U.S. merchants in St. Louis. The growing Santa Fe trade and presence of U.S. merchants allowed many New Mexico elites to prosper and favor closer U.S. relations. New Mexico governor Albino Pérez attempted to enforce the rigid central control favored by Antonio López de Santa Anna. His moral and financial excesses, combined with his imposition of the tenets of the centralist Constitution of 1836, led to a revolt in August 1837 in which Pérez and sixteen other officials were killed. Most Nuevo Mexicanos desired municipal control or village control in the indigenous tradition.
Yucatán resisted centralist control more intensively than other regions in Mexico. Santa Anna's dictatorship angered the white Yucatecan elite because the national government's authoritarianism infringed on their ability to usurp land and water rights to produce sugar and henequen and to prosper from free trade. Higher tariffs, the stationing of federal troops, and local conscription provoked a successful revolt by 1839.
Yucatán soon broke away from Mexico. In 1841, the Yucatecan legislature created an ultra-federalist constitution. When Santa Anna closed Yucatecan trade with Mexican ports, the Yucatecans hired a fleet of warships from the Texas navy. This step later resulted in harmonious ties with the U.S. Navy during the U.S.-Mexican War. Meanwhile, the governor declared the "sovereign nation" of Yucatán. In December 1843 a compromise--the convenios agreement--was agreed to in Mexico City whereby Yucatán was allowed some autonomy. The Mexican government violated the deal by decreeing that major Yucatecan products could not be exported duty free, and Yucatán declared its independence two weeks after the national congress formally repudiated the convenios in December 1845.
A month later Campeche revolted successfully against the state legislature in Mérida in order to protects its merchant fleets from U.S. naval forces. Backed by Maya supporters, Campeche leaders took over Yucatán in January 1847 and did not resist the U.S. occupation of the ports of Laguna and Carmen. But the outbreak of a Maya revolt resulted in the wholesale slaughter of several hundred thousand inhabitants of Yucatán, which led the governor of Yucatán to offer its sovereignty to the United States. Elsewhere in the southeast, the states of Chiapas and Tabasco considered union with Guatemala.