U.S. union leaders in the Federation of Organized Trades and Labor Unions (FOTLU) adopted a plan to make eight hours the standard workday, backed by a nationwide push on May 1, 1886. The decision helped turn a long-running demand for shorter hours into a coordinated, time-specific campaign.
On May 1, 1886, large numbers of workers across the United States struck and marched to demand an eight-hour day. Chicago became one of the most important centers of action, setting the stage for escalating conflicts between workers, employers, and police.
On May 3, 1886, conflict at the McCormick Harvesting Machine Company in Chicago led to deadly violence during an eight-hour-day strike. Organizers then called a protest meeting at Haymarket Square for the next evening, linking workplace killings to the broader campaign for shorter hours.
On May 4, 1886, a rally at Haymarket Square began peacefully in support of the eight-hour day. As police moved to disperse the crowd, a bomb was thrown; gunfire followed, killing police and civilians and injuring many others. The event quickly became an international symbol of labor conflict and state power.
On May 5, 1886, Wisconsin National Guard troops fired on marchers in Milwaukee’s Bay View area during eight-hour-day protests. The killings demonstrated that the struggle for shorter hours—and official violence against workers—extended beyond Chicago.
The criminal trial of the accused Haymarket anarchists began in late June 1886. The case became widely publicized, and debates over evidence, fair juries, and political bias tied the eight-hour movement to broader questions about civil liberties and labor organizing.
In August 1886, the jury found eight defendants guilty, sentencing seven to death and one to prison. The verdict strengthened international campaigns that connected the fight for the eight-hour day with demands for due process and political reform.
On November 11, 1887, four convicted men were executed, after Louis Lingg died by suicide the day before and two others had their sentences commuted to life imprisonment. The hangings became a rallying point for labor activists worldwide and helped keep the eight-hour demand in public debate despite repression.
In July 1889, socialist and labor parties meeting in Paris (the Second International) voted to organize international demonstrations demanding the eight-hour day. The congress adopted May 1, 1890 as a coordinated day of action, tying the eight-hour campaign to a global calendar of labor protest.
On May 1, 1890, workers in many countries staged demonstrations that emphasized the eight-hour day as a central demand. These actions helped establish May Day as a recurring international event, keeping the issue alive even where national laws were slow to change.
On June 26, 1893, Illinois Governor John Peter Altgeld pardoned three surviving Haymarket defendants and sharply criticized the trial’s fairness. The decision reinforced the view among many labor supporters that the Haymarket prosecutions were politically driven, and it kept Haymarket central to the eight-hour movement’s memory and messaging.
In 1894, the Pullman Strike and boycott disrupted rail traffic across large parts of the United States. The federal government used court injunctions and troops to break the strike, showing how hard it could be for workers to win major demands—such as shorter hours—through large-scale action alone.
By late 1915 and early 1916, major railroad brotherhoods formally demanded an eight-hour day with overtime pay, threatening a nationwide strike. This shifted the eight-hour fight toward federal legislation and crisis bargaining, especially as the U.S. government worried about economic disruption.
In early September 1916, Congress passed the Adamson Act to prevent a massive railroad strike. The law established an eight-hour workday and provided for overtime pay for interstate railroad employees, marking a major federal step toward the eight-hour standard—though not yet across all industries.
On March 19, 1917, the U.S. Supreme Court upheld the Adamson Act’s constitutionality in Wilson v. New. The ruling confirmed that Congress could set an eight-hour standard for railroad work under its power to regulate interstate commerce, strengthening the legal path for work-hours regulation.
At the first International Labour Conference in Washington, D.C., the newly created International Labour Organization (ILO) adopted the Hours of Work (Industry) Convention, 1919 (No. 1). This convention put the eight-hour day and a 48-hour week into international labor standards, closing the 1886–1919 arc from protest and repression to formal global recognition.
Haymarket Affair and the International Campaign for the 8-Hour Day (1886–1919)