Today many Americans see Labor Day as time off from work, an opportunity to enjoy a barbecue with friends and family and a final moment of summertime relaxation before the busy fall season begins.

But the history behind the Labor Day holiday is far more complex and dramatic than most might realize, starting with a heated campaign by workers in the late 19th century to win support and recognition for their contributions. In July 1894, President Grover Cleveland finally signed into law legislation creating a national Labor Day holiday in early September—even as federal troops in Chicago brutally crushed a strike by railroad and Pullman sleeping car company workers, leaving some 30 people dead.

More than a decade before the Pullman strike, some 10,000 to 20,000 people joined a parade through Lower Manhattan, organized by New York City’s Central Labor Union on September 5, 1882. "The windows and roofs and even the lamp posts and awning frames were occupied by persons anxious to get a good view of the first parade in New York of workingmen of all trades united in one organization," reported the New York Tribune of that first Labor Day celebration.

Throughout the 1880s, labor strikes became increasingly common, with workers protesting their long hours and difficult, sometimes even dangerous, working conditions. In May 1886, the growing tensions between labor and capital exploded into violence during a protest rally in Chicago’s Haymarket Square. Eight anarchists were eventually convicted on murder charges and four were executed.

After the Haymarket Riot, labor organizers and socialists in countries around the world began celebrating May 1 as Workers Day—an occasion U.S. government officials had no interest in sanctioning. Meanwhile, other cities had followed New York’s lead in holding Labor Day celebrations in early September. In 1887, Oregon became the first state to make it an official holiday; by 1894, 22 other states had passed similar legislation.

In 1893, during a nationwide economic recession, George Pullman laid off hundreds of employees and cut wages for many of the remaining workers at his namesake railroad sleeping car company by some 30 percent. Meanwhile, he refused to lower rents or store prices in Pullman, Illinois, the company town south of Chicago where many of his employees lived.

Angry Pullman workers walked out in May 1894, and the following month, the American Railway Union (ARU) and its leader, Eugene V. Debs, declared a sympathy boycott of all trains using Pullman cars.

The Pullman strike effectively halted rail traffic and commerce in 27 states stretching from Chicago to the West Coast, driving the General Managers Association (GMA), a group that represented Chicago’s railroad companies, to seek help from the federal government in shutting the strike down.

On June 29, some crowd members attending a Debs speech in Blue Island, Illinois, set fires to nearby buildings and derailed a locomotive attached to a U.S. mail train. U.S. Attorney General Richard Olney used the incident as an excuse to ask for an injunction against the strike and its leaders from the federal district court in Chicago, which he got on July 2.

“This was the turning point, because it enjoined the ARU and Debs from doing anything to support or direct the strike,” says Richard Schneirov, professor of history at Indiana State University. “Labor has for much of its history been hemmed in by injunctions, but the Pullman injunction was the first big instance where it really came to the attention of the public.”

The following day, President Cleveland dispatched federal troops to the city to enforce the injunction. Illinois’ pro-labor governor, John Peter Altgeld, who had already called out state militia troops to prevent violence, was outraged, calling the government’s actions unconstitutional. With the arrival of federal troops, the Pullman strike turned bloody, with some rioters destroying hundreds of railroad cars in South Chicago on July 6, and National Guardsmen firing into a mob on July 7, killing as many as 30 people and wounding many others.

Even as Pullman Company and railroad workers were striking, Congress passed legislation in June 1894 making the first Monday in September a federal legal holiday to recognize and celebrate labor. Cleveland signed the bill into law June 28, 1894, a few days before sending federal troops to Chicago.

“It was a way of being supportive of labor,” Schneirov says. “Labor unions were a constituency of the Democratic Party at the time, and it didn't look good for Cleveland, who was a Democrat, to be putting down this strike.”

Federal troops were recalled from Chicago on July 20, and the Pullman strike was declared over in early August. Debs, arrested at the height of the violence along with several other ARU leaders, was charged with violating the injunction and served six months in jail. Though the ARU disbanded, Debs would emerge as the leader of the nation’s growing socialist movement, running for president five times on the Socialist Party ticket.

Aside from the first major instance of “government by injunction” in the struggle between labor and capital, the Pullman strike also marked part of an important transition in American society during the Progressive Era, and a newly active role for the federal government in the nation’s economic and social life.