Violent outbreaks against the Chinese occurred as early as the 1860s and continued to intensify in the 1870s, especially in California. As corporations continued to flood the labor market with Chinese workers, many Chinese were excluded from or refused to join unions in the fight against capital, which angered and threatened the white European immigrants who constituted these organizations. Unions such as the Knights of Labor and the American Federation of Labor supported legislation that limited or excluded Chinese immigration. By the mid-1880s, a wave of anti-Chinese violence grew and spread into the Pacific Northwest.