The significance of the Gold Rush in American history lies in its profound impact on the nation’s economy, demographics, and culture. Beginning in 1848, the California Gold Rush attracted hundreds of thousands of prospectors and settlers, significantly accelerating westward expansion. This influx of people contributed to California's admission as a state in 1850. The Gold Rush stimulated economic growth and innovation, spurring the development of infrastructure such as railroads and telegraphs. It also had lasting effects on Native American populations and led to social changes, including greater diversity as migrants arrived from various countries, shaping the multicultural landscape of the United States.