Mexican Secularization Act of 1833

The Mexican Secularization Act of 1833, officially called the Decree for the Secularization of the Missions of California, was an act passed by the Congress of the Union of the First Mexican Republic which secularized the Californian missions. The act nationalized the missions, transferring their ownership from the Franciscan Order of the Catholic Church to the Mexican authorities.

The act was passed twelve years after Mexico won its independence from Spain in 1821. Mexico feared Spain would continue to have influence and power in California because most of the Spanish missions in California remained loyal to the Roman Catholic Church in Spain. As the new Mexican republic matured, calls for the secularization ("disestablishment") of the missions increased.

Secularization took place for 10 missions in 1834, 6 in 1835, and the other 5 in 1836. Religious services ended, and most priests returned to Mexico. The buildings were stripped of valuables, and left to deteriorate. The rich farmland was not given to the Indians as planned, but was sold or given it away in large grants called ranchos. Secularization also emancipated Indigenous peoples of California from the missions and closed the monjeríos, although only a minority of Indigenous peoples were distributed land grants, which left many of them landless to work the ranchos.