Mike Connolly had a dream: an eight-hour day. A Pennsylvania steel worker for 41 years, he toiled for 12 or more hours a day behind the locked doors of a steel mill with no days off and little hope for the future.

If he worked eight hours a day, he imagined, “I could have a garden, a couple of hundred chickens and know my family…This way one doesn’t want to live long. What is the use of living, since one doesn’t enjoy life?”

Connolly was not alone in his dream. In 1919, hundreds of thousands of workers like him walked off their job in steel mills all around the country. Their strike hampered one of the nation’s largest industries, taking over 365,000 workers off the job and onto the picket lines.

But though the strike was a bold move in a moment of social foment, it was destined to become one of labor history’s most crushing defeats. For workers like Connolly, the Great Strike of 1919 was a huge bust.

At the time, inflation was rampant and social tensions flared. World War I had stoked nationalism, and in October 1917 Bolsheviks had taken over the Russian government and installed a socialist state. This alarmed Americans who worried that socialists in the U.S. might try to violently overthrow the government or seize private businesses.

For many, those fears focused on unionized workers. During World War I, labor had become a crucial part of the war effort, but materials shortages and the draft threatened the nation’s ability to keep up with its labor needs. Tensions ran high between workers and employers. If the United States wanted to win the war, it had to smooth over those disputes.

In response, representatives from labor unions, the government and industrial employers banded together to form the War Labor Board, an entity designed to fend off strikes and mediate in labor disputes. The board brokered a critical deal: Employers promised to improve labor conditions and recognize unions in exchange for a moratorium on strikes. In response, union membership surged.

It was the first time the government had ever protected labor unions, and workers learned to love their improved working conditions. People who had toiled nearly all day long now worked for just eight hours; union members who were used to being attacked by employee-hired thugs when they went on strike now resolved their labor disputes without going on the picket line.

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But almost immediately after the armistice in November 1918, industrial employers made it clear that they expected things to go back to old norms. Unionized steel workers who had been critical to the war effort now faced the same old harassment and intimidation. In Pittsburgh, AFL members found that meeting halls had been shut down for “health violations,” and organizers had run-ins with Pinkerton security officers hired by U.S. Steel.

The company had become an industrial behemoth. It controlled a vast share of the steel market, and was a dangerous place to work. Steel workers faced 12-hour days, exhausting work and harsh discipline. Postwar inflation made it harder to stretch wages. Workers wanted better wages, job protections and improved conditions. But U.S. Steel refused to recognize unions, even though it was the largest employer in the country.

Employers claimed that by organizing, workers were participating in a global socialist takeover. When Seattle ground to a halt during a general strike in February 1919, fears of Bolshevism seemed justified. Meanwhile, steel workers were watching and waiting for the right time to strike.

The AFL, the largest steelworkers’ union, had historically struggled with relatively weak union membership. It was a craft union whose workers organized based on job instead of across industries. During the war, the AFL joined forces with the Amalgamated Association of Iron, Steel and Tin Workers. But working together was challenging: Not only were there the demands of 24 different craft unions to manage, writes historian Douglas M. Eichar, but “workers were divided along ethnic lines, with as many as thirty different nationalities represented in the mills.”

As they struggled to get and stay organized, the groups kept pushing off a strike. Frustrated, some workers who had been galvanized by strikes in other industries quit their unions. Finally, after a referendum, the unions agreed to strike in September 1919.

On September 22, the strike began. Half the steel industry ground to a halt, and workers in six states walked off the job. With as many as 350,000 workers idle, the strike was a major disruption to the industry.

But since it wasn’t wartime, there was no War Labor Board to intervene on behalf of workers. Instead, companies took matters into their own hands, using the media to poison public opinion. They played on racial and ethnic stereotypes, fears of immigrants and the specter of Bolshevism to convince the public that the strikers were opportunists. They also tried to turn workers against one another, pitting immigrant workers against those born in the United States.

“The press groveled at the feet of the steel Gods,” wrote organizer Mary Harris “Mother” Jones in her autobiography. “The public were fed daily stories of revolution and Bolshevism and Russian gold supporting the strike.” Employers attacked the strike’s organizers, branding William Z. Foster, the strike’s main representative, as a dangerous radical. State troopers, local police and company-hired thugs attacked picketers, arresting them en masse, beating them and levying fines for things like “laughing at the police.”

To keep steel production going, the industry brought in tens and thousands of black workers as strikebreakers (most unions turned away black workers). This led to violence and riots, including a massive race riot in Gary, Indiana, that occurred when striking workers attacked black strikebreakers. The riot only ended once state troopers put the town under martial law.

Though state governments were active in the strike, the federal government wasn’t, likely due to the fact that President Wilson had a stroke in September 1919. “Wilson’s advisers held back when he became incapacitated,” explains historian Quentin R. Skrabek, Jr. “Furthermore, Wilson was looking for steel money and support for his League of Nations, and he needed big business.”

Though the Senate did investigate the strike, it, too did nothing. The strike “is entirely the Bolshevik spirit,” mill superintendent W. M. Mink told the Senate committee. “It is not a question of wages.” He blamed the strike on immigrants, calling them “the foreigners” and scoffing at their calls for better wages and an eight-hour day.

George Miller disagreed. A naturalized U.S. citizen, he told the committee that he worked 13 hours at night and 11 in the day, that he was paid 42 cents per hour, and that he could be summarily dismissed if he took time off to deal with sickness in his home. “There is not enough money for the workmen,” he said. “We did not have enough money so that we could have a standard American living.”

Despite those real grievances, the unions simply couldn’t keep up the momentum that had led to the strike in the first place. Infighting, racial and ethnic tensions, and continued negative publicity finally took their toll. Workers even began crossing their own picket lines, fed up with a strike they felt no longer represented their interests. Finally, the AA withdrew from the strike. As plant after plant stopped striking, the AFL could no longer hold the strike. On January 8, 1920, they gave in.

It was a crushing defeat: Both unions saw a vast decline in membership, and employers made it clear that they wouldn’t accept unionization or strikes in the future. And the deep racial and ethnic divisions the strike had stoked paved the way for the nativism of the 1920s. The steel towns that had resisted black workers became havens for the newly revived Ku Klux Klan—an ugly ideological legacy of a strike with idealistic intentions.

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