Haymarket affair

1886 bombing aftermath in Chicago, US

The Haymarket affair was a bombing that took place at a labor demonstration on May 4, 1886, at Haymarket Square in Chicago. The rally began peacefully in support of workers striking for an eight-hour work day; it was held the day after a May 3 rally at a McCormick Harvesting Machine Company plant on the West Side of Chicago, during which police killed two strikers by opening fire at the crowd as it surged to the gate to confront strikebreakers. Many others were injured.

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