On the evening of May 4, two to three thousand workers gathered in Chicago’s Haymarket Square to protest the killing of two strikers by police at the McCormick Reaper plant the day before. Despite their anger, they didn’t become violent but listened peacefully to three speakers who urged them to continue their fight for socialism and an eight-hour day. Pacing through the crowd was Chicago’s mayor, Carter Harrison, who decided the meeting was no cause for worry and went home to bed. So, too, when it began to rain, did all of the women and children and most of the men, until all that remained was a cluster of two to three hundred. The last speaker, Samuel Fielden, a former Methodist minister, was just concluding his remarks.

But a few blocks away at the Desplaines Street police station, two detectives rushed in to report to Inspector John “Black Jack” Bonfield that Fielden was using “inflammatory language.” Bonfield was not a man given to lengthy deliberation, nor could he have been described as sympathetic to the labor movement. That very evening, according to one witness, he had confided that “the greatest trouble the police had in dealing with the Socialists was that they had their women and children with them at the meetings so that the police could not get at them. [Bonfield] said he wished he could get a crowd of about three thousand of them together, without their women and children, and he would make work of them.” Upon hearing his detectives’ report, the inspector seemed to have thought his opportunity had arrived. In the next moment he was racing his squad of policemen down to the square at a run. Arriving at the wagon on which Fielden stood, he shouted, “I command you, in the name of the people of the state of Illinois, immediately and peaceably to disperse!” Fielden protested that they were peaceable, but then relented and agreed to leave.

That was the moment someone—it was never learned who—chose to throw a bomb. It landed among the policemen, and the ensuing explosion rocked the street. After a stunned silence, the policemen grabbed their guns and fired recklessly into the crowd—and into each other. According to the Chicago Tribune , a police official acknowledged that “a very large number of police were wounded by each other’s revolvers.” There was no evidence that the workers ever fired back. When the Haymarket Riot ended, seven policemen were fatally wounded. No count was taken of civilian casualties, but according to the Chicago Herald , some fifty lay dead or wounded in the streets.

That was just the beginning of the Haymarket affair. Within the next few weeks, the police indiscriminately arrested anyone known as a radical. Thirty-one people were indicted, and eight were brought to trial. None of the eight were found guilty of throwing the bomb, but they were convicted by a hysterical public, an