Haymarket, Homestead, and Pullman were all violent labor strikes.
The Homestead Strike occurred in 1892 in Homestead PA and was a violent battle between laborers and hired Pinkertons after a lockout.
The Haymarket Affair occurred in Chicago in 1896 and involved a violent labor protest and a bombing.
The Pullman Strike occurred in 1894 and was a nationwide violent railroad strike.