I.

Introduction

Haymarket Square Riot, confrontation between police and protesters that took place on May 4, 1886, in Haymarket Square in Chicago. The event became a famous landmark in United States labor history and took on symbolic importance around the world as a key event in the labor movement’s struggle for the eight-hour workday. The riot and the trial that followed of eight anarchists accused of conspiracy also raised questions about American attitudes toward immigrants and civil liberties in periods of social crisis. See also Hours of Labor; Labor Unions in the United States.