1. In 1786, Spanish missionary Juan Crespi arrived in San Diego, beginning a journey to establish the Mission system in California. Crespi was a member of the Gaspar de Portolá expedition that sought to find Monterey Bay and establish settlements along the way.

2. In 1846, the Bear Flag Revolt began in Sonoma, California. A group of American settlers seized control of the town and declared California independent from Mexico. The revolt lasted only a few weeks before the US military took over the region, but it marked the beginning of California's transition from Mexican to American control.

3. In 1941, the USS Arizona Memorial was authorized by Congress. The memorial honors the 1,177 sailors and marines who died when the USS Arizona was sunk during the Japanese attack on Pearl Harbor. The memorial was built over the remains of the ship and is one of the most visited tourist attractions in Hawaii.

4. In 1966, the Rolling Stones performed a concert at the Altamont Speedway in Livermore. The concert was marred by violence, including the stabbing of a concertgoer by a member of the Hell's Angels motorcycle gang who had been hired as security. The Altamont concert has been called the end of the "peace and love" era of the 1960s.

5. In 1980, a magnitude 7.2 earthquake struck the Mammoth Lakes area of California. The earthquake was the largest to hit the region in over 50 years and caused extensive damage. The earthquake also triggered a series of aftershocks and caused a geothermal eruption that created a new hot spring in the area.