When did California gain admission into the United States?

California gained admission into the United States on September 9, 1850, becoming the 31st state to join the Union. This event was significant not only for California but also for the broader context of American history, as it occurred during the time of westward expansion and following the Gold Rush, which accelerated the influx of settlers into the region.

The date marks California's transition from being a territory acquired through the Mexican-American War (1846-1848) to a fully recognized state within the United States, highlighting the changing political landscape of the country during the mid-19th century. This admission was part of the Compromise of 1850, a series of laws aimed at balancing the interests of free and slave states, which played a crucial role in the events leading up to the Civil War.

The other dates provided in the choices do not correspond to California's statehood, reflecting events much earlier or much later than its actual admission. For example, July 4, 1776, is celebrated as Independence Day, marking the adoption of the Declaration of Independence. January 1, 1900, and March 15, 1855, do not have any specific historical significance regarding California's status as a state