In January of 1848, James Wilson Marshall discovered gold in a river near Sacramento, California. The find of gold was reported in March editions of newspapers in San Francisco, but no one paid much attention as it was all thought to be a hoax.
In May of 1848, Sam Brannon came through San Francisco with a bottle filled with gold, yelling about the discovery in the river. With proof, the rush began.
San Francisco's harbor was cluttered and the two main newspapers were shut down, as the full staff were away trying to make a fortune in the gold fields.
In August, news of gold reached the East Coast as the New York Herald printed the discovery. A census of San Francisco in April reported 79 buildings considered homes. By December 1849, that figure was 300,000. Due to this influx of Americans into California, the once-predominantly Mexican colony was turned American and thus ushered in the state's place in the union.