May 1 is International Workers’ Day. Also known as “May Day,” its origins trace back to 1856 in Australia, where workers organized a day of stoppages and celebrations to demand an eight-hour workday. However, May 1 didn’t become a widespread international day for labor until after the infamous Haymarket Affair of 1886.

Workers in Chicago, including many immigrants, went on strike on May 1 to demand the eight-hour workday. At least four strikers were killed while picketing the McCormick Harvester factory, at that point the largest factory in the world. A large rally was held on May 4 to protest violence against peaceful picketers. As police moved to disperse the crowd, someone threw a bomb that killed seven officers. Police fired back indiscriminately, wounding and killing an undetermined number of workers.

What followed was a sweeping crackdown: police raids, the arrests of hundreds of men and women, and the indictment of eight people—five of whom were German immigrants. The partisan judge Joseph E. Gary conducted the trial where all 12 jurors acknowledged prejudice against the defendants. All defendants were convicted with no evidence and seven were sentenced to death; four were hanged, one died by suicide, and two had their sentences commuted. The trial is widely considered a miscarriage of justice.

In the aftermath, socialists and unionists worldwide began marking May 1st as a day of international worker solidarity. However, in 1894, U.S. President Grover Cleveland—looking to make peace with labor prior to the midterm elections after more than 30 workers were killed during the Pullman Strike—established Labor Day in early September. He did this explicitly to avoid associating it with May Day and the labor unrest it represented. In 1955, at the height of the Cold War, President Eisenhower proclaimed May 1 “Loyalty Day” instead of “May Day” in response to the holiday’s popularity in communist countries.

Labor unions today

Now 140 years after Haymarket, workers are still fighting for higher pay, better working conditions, and a voice on the job. In recent decades, policymakers have done little to stem the relentless tide of anti-union actions by employers, conservative governments, and a hostile Supreme Court. As workers’ rights have been eroded, the share of unionized workers fell from over 30% in the 1950s to just 11.2% in 2025. Fewer workers were involved in major strikes or work stoppages in 2025 (307,000) than during the Haymarket year of 1886 (610,000).

Nonetheless, there are clear signs of momentum in the labor movement. The post-pandemic period has brought a notable resurgence in labor’s popularity and organizing activity. Figure A shows that 68% of Americans now approve of labor unions, levels not seen since the 1960s. Unions are also more highly regarded among young people. Further, 43% of Americans want unions to have more influence in the country, a record high.

Not only are unions more popular, but more workers have been trying to join a union. Figure B shows that the 2024–2025 period saw the highest number of newly unionized workers since at least 2000.

Indeed, while the Trump administration has taken a decidedly hostile approach to unions and made labor organizing more difficult, union representation in the United States increased by 463,000 in 2025. More workers were represented by a union than at any point in the past 16 years, a sign that workers see unions as a means of resisting authoritarianism.

The time is ripe for policymakers to support workers’ struggles for dignity and respect. Key policies such as passing the Protecting the Right to Organize Act, ensuring workers can reach a first contract, expanding collective bargaining rights, and eliminating anti-union “right-to-work” laws can help workers organize their workplaces. Beyond improving the lives of their members, unions have spillover effects that benefit whole communities and democracy.

This May Day, workers and their unions across the country are holding thousands of events, encouraging participants to join an economic blackout and “demand a nation that puts workers over billionaires.” Just as workers around the world came together to demand fair hours and wages after the events of 1886, we can hope the workers of the future will find inspiration from May Day 2026.