Despite the myth of a virgin country conquered during the Gold Rush in mid-XIXth century, the history of California is far more complex.
As often concerning America, the best starting point to understand it is Christopher Columbus's landing in 1492.
Thirty years later, following the conquest of the Aztec empire by Hernán Cortés in 1521, the Spanish crown created the kingdom of New Spain, which was transformed into a viceroyalty in 1535.
Cities were established one after the other: Mexico city, near Tenochtitlán, the old capital of the Aztecs, Veracruz, Guadalajara. etc.
At the end of the XVIIIth century, the territory claimed by New Spain covered Mexico, a part of central America to the south, a large chunk of present-day United States to the north, Cuba and Hispaniola, the Philippines in the Pacific ocean, and other miscellaneous islands.
The Spanish empire, which encompassed other viceroyalties, extended, of course, over a much greater area.
Beginning in the XVIth century, catholic missions had begun to be established all over New Spain. They sprang up in Mexico, Florida, Texas, Trinidad, etc.
As regards California, Jesuits began to found missions in Baja California in 1683. This is the name of the long narrow peninsula on the northwestern coast of Mexico.
In mid-XVIIIth century, king Philip V of Spain, fearing the threat of Russia over the western coast of North America, ordered mission settlements in Alta California as well - that is, present-day California.
After the ban of Jesuits by Charles III and eventually by the Pope in 1767, the Franciscans took over the missions development.
Franciscan friar Junípero Serra (1713, Majorca, Spain - 1784, Monterey, California) founded the first mission in Alta California in 1769, at a location which came to be known as San Diego. The second was installed in 1770 in what became Carmel, and was followed by nineteen more.
The official purpose of these missions was to greet natives into Christianity. It was also a way to take physical control of the region. This explains why they were structured like self-sustaining garrisons. They nonetheless left a beautiful architectural legacy.
After three hundred years of existence the Spanish holdings overseas no longer formed a strong empire. Florida had been lost to the British in 1763. The vast territory of Louisiana was ceded to Napoleon who in turn sold it to the United States in 1803.
Louisiana roughly spanned the middle third of present-day U.S. and should not be confused with the state of Louisiana of our days.
Mexico became independent from Spain in 1821. Then, encouraged by the United States, Texas became independent from Mexico in 1836.
The Mexican American war of 1846-1848 resulted in Alta California, together with Arizona and New Mexico, becoming part of the United States.
The ink of the treaty was not yet dry when Johann Sutter (1803-1880) discovered gold on his large estate, named New Helvetia, near Sacramento.
This launched the Gold Rush of 1848-1855. San Francisco turned from small town to big city. California was settled by pioneers arriving via the California Trail and other routes. And it began to develop, at first into an agricultural state.
The rest, as they say, is history.
But the Spanish missions were the seeds of all the major cities of California and provided its first economic spine.
This is why they play such an important historical and cultural role in the memory of modern California.