An infamous labor protest in Chicago in 1886 that resulted in chaos and violence. The protests lasted for 8 days
The Haymarket Square Riot (sometimes called the Haymarket Massacre) started as a demonstration for an 8-hour workday. The protest went on for several days. On the last day, an unknown person threw a bomb into the crowd of police officers and the police opened fire. 8 police officers and an unknown number of civilians were killed.
The chaos of the riot resulted in bad public opinion toward labor unions and was one of the reasons for the fall of some labor unions at the time. It is also a prime example of how far separated the working class was from the upper classes.