The California Gold Rush (1848–1855) began on January 24, 1848, when gold was discovered by James Wilson Marshall at Sutter's Mill, in Coloma, California. News of the discovery soon spread, resulting in some 300,000 men, women, and children coming to California from the rest of the United States and abroad. Of the 300,000, approximately 150,000 arrived by sea while the remaining 150,000 arrived by land.
These early gold-seekers, called "forty-niners," (as a reference to 1849) traveled to California by sailing boat and in covered wagons across the continent, often facing substantial hardships on the trip. While most of the newly-arrived were Americans, the Gold Rush attracted tens of thousands from Latin America, Europe, Australia, and Asia. At first, the prospectors retrieved the gold from streams and riverbeds using simple techniques, such as panning. More sophisticated methods of gold recovery developed which were later adopted around the world. At its peak, technological advances reached a point where significant financing was required - increasing the proportion of corporate to individual miners. Gold worth billions of today's dollars was recovered, which led to great wealth for a few. However, many returned home with little more than they started with.
The effects of the Gold Rush were substantial. San Francisco grew from a small settlement to a boomtown, and roads, churches, schools and other towns were built throughout California. A system of laws and a government were created, leading to the admission of California as a free state in 1850 as part of the Compromise of 1850.
New methods of transportation developed as steamships came into regular service and railroads were built. The business of agriculture, California's next major growth field, was started on a wide scale throughout the state. However, the Gold Rush also had negative effects: Native Americans were attacked and pushed off traditional lands, and gold mining caused environmental harm.