The Haymarket Affair, which took place in 1886 in Chicago, was significant in labor history as it marked a turning point in the labor movement’s struggle for workers' rights, particularly the fight for an eight-hour workday. The event began as a peaceful rally in support of striking workers when a bomb was thrown, leading to violence and a police crackdown. In the aftermath, a highly publicized trial convicted several anarchists, although the actual perpetrators remained unknown. This incident heightened tensions between labor activists and the state and is often commemorated as a symbol of workers' struggles worldwide.