The violent riots resulted from growing anti-Asian sentiment among White populations during the late 19th and early 20th centuries.
[1] During the late 19th and early 20th centuries, the Pacific coasts of both the United States and Canada experienced waves of Asian immigration.
[2] Immigration trended upwards as the 19th century came to a close, as well as the Nativist political movement among White Canadians and Americans.
Led by Californian Nativists who violently attacked Japanese immigrants with the goal of socio-economic exclusion and school segregation, these violent riots led to a series of negotiations between the governments of the United States, Canada, and Japan, which culminated with the Gentlemen's Agreement.
[5] Just two days later, the Vancouver riot spanned September 7–8, ultimately as a response to White concerns with the growing Asian population over the summer of 1907[citation needed].