Which 1886 Chicago labor event helped inspire International Workers’ Day?

The Haymarket affair helped inspire International Workers’ Day.

The event began with a labor rally in Chicago’s Haymarket Square on May 4, 1886. The meeting was held during a nationwide campaign for an eight-hour workday. After police moved to disperse the gathering, someone threw a bomb, and gunfire followed. Police officers and civilians died or were injured.

Eight anarchists were arrested and tried, although the evidence linking them to the bombing was widely disputed. Several were executed, while others received prison sentences or were later pardoned. The affair became an international symbol of conflict between workers, employers, and state authorities.

Its connection is primarily with May 1 observances, not the U.S. September Labor Day. The Pullman Strike, Homestead strike, and Ludlow Massacre were separate labor conflicts with different dates and circumstances.