Read the following passage and answer the question that follows.
Many people have heard of the California gold rush, which took place in the 1840s and 1850s, less than a century after the United States declared its independence. However, fewer realize that the gold rush was started by only two men—two men who would end up having a huge impact on the demographics of the state. While constructing a sawmill for John Sutter, the founder of a colony near Coloma, California, that he called Nueva Helvetica, carpenter John Wilson Marshall saw gold flakes in the American River. Marshall and Sutter decided that they wouldn’t share the news with anyone, but the resolution didn’t hold for long. Sutter’s discovery occurred in January 1948; by the middle of March, the presence of gold on Sutter’s land had made it into the newspapers.
Still, most people did not believe the news, until one man took a vial containing gold he’d found at “Sutter’s Creek” through the streets of Nueva Helvetica. The impact of this one event was enormous: three months later, 75% of men from San Francisco (at the time, known as Yerba Buena) were working in the gold mines. There were more than 4,000 people panning for gold by August of that year, when the New York Herald reported the discovery.
The Herald‘s announcement proved to be the tipping point of the gold rush. Many people gambled significant amounts of money and property on the venture, borrowing, mortgaging homes, and leaving their families to find their fortune in California. A reported 30,000 people traveled west across the United States to California in the spring of 1849 alone. Others traveled by water, an immense undertaking that involved sailing through Panama or even around the southern end of South America.
According to the passage, what was the major significance of the California gold rush?