| 1533 | Spanish Ships Landed in Baja | The first Spanish ships landed in Baja, California in 1533. Very little is known about this landing, and native peoples responded with aggression. |
| 1535 | Hernando Cortez Visited | Hernando Cortez visited California in 1535; he made early attempts at colonization and settlement. These early settlements were unsuccessful. |
| 1540 | Hernando de Alarcon Reached Land in California | On a sea expedition, Hernando de Alarcon, under the directive of the Viceroy of Spain, and his crew sailed up the Colorado River. They were the first Europeans to stand on California soil. |
| September 28, 1542 | Juan Rodriguez Cabrillo Explored California | The Portuguese explorer Juan Rodriguez Cabrillo landed in San Diego. He was the first European to explore California. |
| 1579 | Sir Francis Drake Landed in San Francisco Bay | In 1579, the British explorer Sir Francis Drake landed in north of modern-day San Francisco. He claimed California for Britain. |
| 1665 | Spanish Colonization of California Began in Earnest | The Spanish colonization of California began in 1665 with the arrival of Jose de Galvez in Mexico. De Galvez made plans to colonize California; however, he was insane and frequently delusional. His plans would not be accomplished for another century. |
| 1769 | San Diego del Alcala, First Spanish Mission Founded | The first Spanish Mission, or religious institution designed to convert and control native peoples, was built in San Diego by Franciscan friar Junipero Serra. |
| 1776 | Foundation of Presidio of San Francisco | The Presidio of San Francisco was founded in 1776. Mission Delores is considered the first historical landmark in the city of San Francisco. |
| 1820 | Traders from the East Coast Began to Visit California | Around 1820, the first traders from the East Coast began to visit California, typically in search of beaver and otter fur. Later, a small number of settlers entered California, some intermarrying with Mexican women. |
| 1821 | Mexico Gained Independence from Spain | Mexico gained independence from Spain in 1821. California was now under the control of the Mexican government, rather than the Spanish. |
| December 1846 | United States Invaded Mexico | The United States invaded Mexico in 1846, reaching San Diego in December of that year. In July of that year, the United States had planted its flag on Mexican soil. |
| 1848 | Gold Rush Began | The gold rush began in January 1848 with the discovery of gold at Sutter's Sawmill in Coloma, California. The following year, a huge number of settlers moved to California in search of riches. |
| September 9, 1850 | California Statehood | California became the 31st U.S. state in 1850. With the riches of the gold rush, statehood was rushed, with less bureaucracy than normal for other territories. |
| 1860 | Pony Express Began | The Pony Express began offering rapid mail service between Missouri and California. This enabled much faster communications. |
| 1869 | First Westbound Train Reached San Francisco | With the completion of the rail lines, the first Westbound train reached San Francisco. California was now far more accessible than ever before. Rather than having to travel in dangerous wagon trains, the railroads offered a safe and practical way to move across the country. |
| 1910 | Opening of Angel Island | Angel Island, California's immigration hub, comparable to Ellis Island, opened in 1910. In addition to serving as a centralized location for immigrants, Angel Island was also a prison for Chinese immigrants, largely banned by the Chinese Exclusion Act of 1882. |
| May 27, 1937 | Opening of Golden Gate Bridge | The Golden Gate Bridge, today one of San Francisco's best-known landmarks opened to traffic on May 27, 1937. |
| 1942 | Internment Camps Created | Executive Order 9066, signed by U.S. President Roosevelt created the first internment camps for individuals of Japanese or German origins. The largest Japanese population in the United States was in California. |
