Twenty years of labour struggles in Chicago, fueled by a mix of industrialization, racism, and post-World War I economic depression, left over thirty people dead and thousands burned out of their homes during the summer of 1919. Chicago became the major meat-processing centre in the United States of America during the late nineteenth and early twentieth centuries. The Chicago River played an important part in the history of the city, helping the meat processing industry set-up shop and, with the help of the railroads, to grow. New industrial techniques and inventions brought radical changes to the meatpacking business, but working conditions and wages for workers deteriorated. Unions tried to address these issues. Ethnic and racialized divisions in the labour force hobbled union efforts, and meatpacking companies exploited the situation. The end of World War I meant the end of lucrative government contracts for meatpacking companies, and the economic depression that followed increased tensions in the workforce. Intensified racism and violence in the South caused African-Americans to migrate to Chicago, giving the meat-packers a larger workforce to use against unions. The labour market tensions cultivated by Chicago meatpacking companies ignited on July 27, 1919 and resulted in the Chicago riots, which became part of Red Summer, one of the bloodiest chapters of racialized tension in American history.