Answer: The Gold Rush
The effects of the Gold Rush were substantial. San Francisco grew from a small settlement of about 200 residents in 1846 to a boomtown of about 36,000 by 1852. Roads, churches, schools and other towns were built throughout California. In 1849 a state constitution was written, a governor and legislature chosen and California became a state in 1850 as part of the Compromise of 1850.