The Presidios: Spanish Outposts in Alta California

 
1820 Map of the Presidio at San Diego
Ruins of the San Diego Presidio

The 21 California missions were established by the Franciscan Order of the Catholic Church in order to spread their faith throughout California. However, the building of the missions was strongly supported by the Spanish government, which saw in the missions a way to expand the Spanish sphere of influence.

Each mission formed the core of a settlement, many of which eventually grew into California’s major cities. The missions were protected by small contingents of soldiers.

These small detachments were not sufficient to secure Spain’s interests in Alta California. The Spanish feared that other countries – especially Russia – had designs on its North American territories. In addition, there was a constant fear of pirates raiding the coastal missions and settlements.

The Spanish government therefore divided Alta California into four military districts, each controlled and protected by a military fort, or presidio.

Later, after Mexico declared its independence from Spain, a fifth presidio was built at Sonoma. This presidio became the headquarters for the Mexican army in California, and the other presidios were reduced to small garrisons.

The five presidios, in order of their construction, were:

El Presidio Real de San Diego

San Diego - July 16, 1769

The first of the presidios, it formed the base for Spain’s expansion into California. It was ultimately responsible for the defense of the missions at San Diego, San Luis Rey, San Juan Capistrano, and San Gabriel.

El Presidio Real de San Carlos de Monterey

Monterey - June 3, 1770

Responsible for the defense of the missions at San Luis Obispo, San Miguel, San Antonio, Soledad, San Carlos, and San Juan Bautista.

El Presidio Real de San Francisco

San Francisco - December 17, 1776

Responsible for the defense of the missions at Santa Cruz, San José, Santa Clara, San Francisco, San Rafael, and Solano.

El Presidio Real de Santa Bárbara

Santa Barbara - April 12, 1782

Reponsible for the defense of the missions at San Fernando, San Buenaventura, Santa Barbara, Santa Inés, and La Purísima.

El Presidio de Sonoma

Sonoma - 1810

The final presidio, at Sonoma, was built after Mexican independence from Spain. It was intended to act as a military buffer against Russian settlements, which had reached as far south as Fort Ross. The Sonoma presidio became the headquarters of the Mexican Army in California, while the remaining presidios were abandoned and, in time, fell into ruins.