I know there were a few mass influxes of Chinese immigrants to the west coast around the turn of the 20th century, and probably earlier? Were there journal anecdotes, etc. from residents in coastal cities about the introduction of or increase in east asian cuisine in markets and other public spaces?
Have you see this movie? http://www.thesearchforgeneraltso.com/ I really recommend it. Its on Netflix. Due to the Chinese Exclusion Act of 1882 Chinese Immigration was frozen and the Chinese already living had to find ways of subsisting on their own. Many opened laundrys and also restaurants. The oldest dishes were Chop Suey, beef and broccoli and shredded beef. The movie covers this pretty well.