It's the Economy, Stupid

Chinese immigrants flooded into California for the plentiful jobs in the 1850s and 1860s. The Gold Rush was making it rain. Which, when you're talking about gold, can be dangerous since gold is like, really heavy.

Then the Panic of 1873 hit, and there were no more jobs. Though most estimates put the Panic (which was called the Great Depression until the 1930s rolled around) over by 1879, that kind of financial disaster is going to impact policy for a couple years after it's officially "over."

The law had some bearing in economic reality, although it does call into question what the role of government is. Basically, an influx of Chinese laborers who are willing to work for less than their white counterparts is going to decrease wages and drive white guys out of jobs. These guys wanted the government to protect their jobs by getting rid of the Chinese.

Makes a weird amount of sense, if you look at it in that way…and absolutely no other way.