What was the Gold Rush primarily characterized by?

The Gold Rush was primarily characterized by mass migration to California for gold. This significant event began in 1848 when gold was discovered at Sutter's Mill, prompting a massive influx of people from various parts of the United States and beyond. The promise of wealth attracted not only gold seekers but also individuals hoping to start new lives, leading to a population surge in California. Towns sprang up rapidly, and the social and economic landscape was transformed.

As people poured into California, it became clear that the Gold Rush was not just a local phenomenon; it had national and even international implications, as fortune-seekers from countries such as Mexico, China, and Europe were drawn to the region. This migration greatly contributed to California's rapid admission into the Union and influenced the development of the West.

While other options mentioned are true to some extent, they do not capture the essence of what characterized the Gold Rush as profoundly as the mass migration did. The establishment of whaling industries and significant immigration from Japan occurred in different contexts and times, and the decline of agriculture is not a defining feature of the era resulting from the Gold Rush but rather a consequence of other economic changes.