Mission La Purísima was originally established at a site known to the Chumash people as Algsacpi and to the Spanish as the plain of Río Santa Rosa, one mile south of Lompoc.

The original mission had many rooms for the two priests, the evangelized Chumash and for a chapel, six soldiers, married Indians and unmarried females.

The original mission was south of the Santa Ynez River and included vast crop and grazing lands.

The California State Historical Landmark reads: Mariano Payeras received permission to relocate the mission community 4 miles (6.4 km) to the northeast in La Cañada de los Berros, next to El Camino Real.

[19] After Mexico won the Mexican War of Independence in 1823, Spanish funding ceased to the Santa Barbara Presidio.

The Mexican government, which had gained independence from Spain, transferred control of the missions from the Catholic Church to civil authorities.

The property passed into private ownership and the mission buildings fell into ruin; the lands were granted to the Rancho Ex-Mission la Purisima.

In the 20th century, under direction of the National Park Service, the Civilian Conservation Corps (CCC) pledged to restore the mission if enough land could be provided to convert it into a historic landmark.

[19] The Catholic Church and the Union Oil Company donated sufficient land for the CCC to proceed with the restoration.

The nine buildings as well as many small structures and the original water system were fully restored with the mission's dedication occurring on December 7, 1941, the same day the United States entered World War II.