Although pioneers and mountain men had been steadily moving westward for at least two decades prior to 1849, the discovery of gold at the construction site of a mill in California triggered the first great boom in the West. Within a year of the discovery, the population of white settlers in California had risen from 20,000 to 100,000.
Unlike those who had followed the Oregon Trail westward in the previous decades in hopes of establishing farms, most of the people who moved west as a result of the California gold rush were miners in search of a fast path to wealth. Those who moved to California in search of gold became known as '49ers, and the population boom also spurred the West's reputation for lawlessness. Thousands of men who had left their families behind took up drinking, soliciting prostitutes and gambling.
The gold rush also aided in the establishment of steady industrial economies in the West that were able to continue thriving even once gold became scarce. Those miners who didn't strike it rich from gold eventually either settled into the population of the booming California towns and took on industrial jobs or settled as farmers in the surrounding countryside. Others returned home to their families.