for their willingness to do anythingng at any weight to survive. the 1880s to the chinese solution act. a it's the only immigration law specifically targeted as a group. especially after that group instrumentally how to build the transcontinental railroad. from the east coast to the west coast. thousands of chinese immigrants die for doing that. the minute they finish their work they were pushed out. they were told they could never become citizens of the country. >> how long was that exclusion act in place? >> exclusion act lasting until the second world war to this end of the second world war when the united states became his allies with china. that's when the united states decided to cancel the act. >> now, you report from 1790 until 1870 about 9 million immigrants came into the country. after that didn't slow down or speed up? >> it definitely slowed down. this is why it is important for a way for immigrants. factor from immigrant home country is normal because there's economic devastation. or persecution for religious persecution people wanted