1. St. Patrick's Day Festivities: St. Patrick's Day is celebrated every year on March 17th and is a big event in California. The streets of San Francisco, Los Angeles, and other cities come alive with green on this day. The famous San Francisco St. Patrick's Day Parade, which started in the 1850s, is the largest in the Western United States.

2. Mission San Luis Obispo de Tolosa: On March 17, 1772, the Mission San Luis Obispo de Tolosa was founded. This was the fifth mission established by Father Junipero Serra and was located in what is now San Luis Obispo, California. The mission was built to serve the local Chumash people.

3. Earthquake in Southern California: On March 17, 1990, a 5.2 magnitude earthquake struck southern California. The epicenter was near the town of Big Bear Lake, and the quake caused some damage to buildings and roads in the area. Thankfully, no one was killed or seriously injured.

4. Kennedy Space Center Bombing: On March 17, 1978, a group of terrorists bombed the Kennedy Space Center in Florida. The members of the group, who were protesting the US Navy's involvement in nuclear weapons, were responsible for millions of dollars in damage. This event demonstrated the danger of militant anti-nuclear activism.

5. Governor Jerry Brown Launches Primary Campaign: On March 17, 2010, Governor Jerry Brown officially launched his primary campaign for the California gubernatorial race. Brown went on to win the election and became the oldest person to be elected as California's governor.