In 1860 there were only about 1,800 Chinese women in all of the United States, but about 33,000 Chinese men.
Most of the Chinese women did not come to America by choice.
The majority were kidnapped, tricked, or bought (supposedly as servants) from their families and then sold as prostitutes in America.
In the mid-1870s Protestant women missionaries periodically raided the houses of prostitution to rescue the young girls and try to convert them to Christianity.
In 1875 a new federal law, designed to keep Chinese women prostitutes out of the country, had the effect of keeping almost all Chinese women out.