The "Gold Rush" refers to a period in the mid-19th century when thousands of people flocked to areas like California in search of gold. It began in 1848 when gold was discovered at Sutter's Mill, leading to a massive influx of prospectors, known as "forty-niners." These hopeful miners dreamed of striking it rich, often facing harsh conditions and competition. As the rush continued, towns sprang up almost overnight, transforming the landscape. While some found wealth, many others struggled and faced challenges like disease and lawlessness. The Gold Rush significantly impacted American history, shaping the economy and leading to the expansion of the western frontier.