Haymarket massacre is the huge bombing s and explosions on the labours who were on a rally demonstrating their protest. It took place on the roads of Chicago.
Step-by-step explanation:
Haymarket square is the common and a busy place in Chicago and many laborers were rallying on the streets demanding lesser working hours. They were oppressed and exhausted to work for long hours and the labours demonstrated their protests by rallying on the streets of Chicago.
A dynamite bomb was thrown by an unknown person on the group of people and it resulted in the death of civilians and police officers. Many laborers who participated in the protest died in a gruesome manner. This event of brutality kindled the emotions of the laborers world-wide and initiated the labor movement. May Day is celebrated commemorating the death of laborers who struggled for better pay and working hours.