Mission Indians are the indigenous peoples of California who lived in Southern California and were forcibly relocated from their traditional dwellings, villages, and homelands to live and work at 15 Franciscan missions in Southern California, and the Asisténcias and Estáncias established between 1796 and 1823 in the Las Californias Province of the Viceroyalty of New Spain.
Spanish explorers arrived on California's coasts as early as the mid-16th century. In 1769 the first Spanish Franciscan mission was built in San Diego. Local tribes were relocated and conscripted into forced labor on the mission, stretching from San Diego to San Francisco. Disease, starvation, over work, and torture decimated these tribes. Many were baptized as Roman Catholics by the Franciscan missionaries at the missions.
Mission Indians were from many regional Native American tribes; their members were often relocated together in new mixed groups and the Spanish name d the Indian groups after the responsible mission. For instance, the Payomkowishum were renamed Luiseños after the Mission San Luis Rey, and the Acjachemem were renamed the Juaneños after the Mission San Juan Capistrano. The Catholic priests forbade the Indians from practicing their native culture, resulting in the disruption of many tribes' linguistic, spiritual, and cultural practices. With no acquired immunity to the new European diseases, and changed cultural and lifestyle demands, the population of Native American Mission Indians suffered high mortality and dramatic decreases especially in the coastal regions where population was reduced by 90 percent between 1769 and 1848.