Indigenous peoples of Mexico
When Mexico gained independence in 1821, the casta system was eliminated as a legal structure, but racial divides remained. 
White Mexican argued about what the solution was to the "Indian Problem", that is indigenous who continued to live in communities and were not integrated politically or socially as citizens of the new republic. The Mexican constitution of 1824 has several articles pertaining to indigenous peoples. The second article of the constitution of Mexico recognizes and enforces the right of indigenous peoples and communities to self-determination and therefore their autonomy to:
Mexican Cession
Considering the seizures, including all of Texas, Mexico lost 54% of its pre-1836 territory in the Treaty of Guadalupe Hidalgo. For only fifteen years from 1821 (when Mexican independence was secured) and the Texan Revolt in 1836, the Mexican Cession (excluding Texas) formed approximately 42% of the country of Mexico; prior to that, it had been a part of the Spanish colony of New Spain for some three centuries. Beginning in the early seventeenth century, a chain of Roman Catholic missions and settlements extended into the New Mexico region, mostly following the course of the Rio Grande from the El Paso area to Santa Fe.