The enthusiasm for living in California in 1848 significantly changed primarily due to the discovery of gold at Sutter's Mill. This event triggered the California Gold Rush, leading many people to believe they could strike it rich by moving to California. While the end of California's war with the United States and increased awareness of the region's suitability for life contributed to people's interest, the potential for wealth from gold was the most compelling factor that motivated individuals to relocate.
Thus, the statement that best encapsulates the reasons for the change in attitude is:
- There was a possibility of an amazing vast fortune in California due to the discovery of gold.