What do I capitalize? Which is correct in this sentence: California Gold Rush or California gold rush? Please support with the grammatical rule.

Question

The decline of whaling in America began with the California gold rush in 1849.

Answer 1

Most sources capitalize California Gold Rush because it's a specific event in U.S. history, like the Civil War, Reconstruction, and Great Depression.

Answer 2

http://grammar.ccc.commnet.edu/grammar/capitals.htm
See #4 -- historical events

What do you think -- capitals or not?

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