Ludlow Massacre, attack on striking coal miners and their families by the Colorado National Guard and Colorado Fuel and Iron Company guards at Ludlow, Colorado, on April 20, 1914, resulting in the deaths of 25 people, including 11 children.

Ludlow Massacre Ruins of the Ludlow camp in Colorado, 1914. Library of Congress, Washington, D.C.

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About 10,000 miners under the direction of the United Mine Workers of America (UMWA) had been on strike since September 13, 1913, protesting low pay and abysmal working conditions in the coalfields of Colorado. Evicted from the company towns by the operators of industrialist John D. Rockefeller’s Colorado Fuel and Iron Company, striking miners constructed tent colonies, the largest of which housed about 1,200 strikers, in Ludlow. The striking miners were a polyglot of ethnicities, including a large number of Greeks and Italians.

Tensions ran high between the armed strikers and the company-hired detectives. The Colorado National Guard, which had been deployed to reduce violence, favoured the operators by escorting strikebreakers to the mines and overlooking the violent actions of the detectives. Labour activist Mary (“Mother”) Jones led a campaign to bring national attention to the strike.

In April 1914 the cost of maintaining the troops led to a reduction in the National Guard presence, resulting in increased violence. On Sunday, April 19, 1914, the National Guard encircled the Ludlow camp and deployed a machine gun on a bluff overlooking the strikers. Although no one knows exactly what instigated the violence, some accounts suggest that officers of the National Guard demanded that the miners turn over at least one individual, possibly a striker or even a hostage that they were holding, but the miners refused. The National Guard then opened fire on the camp, initiating a pitched battle that lasted throughout the day. Three of the striking leaders, including labour organizer Louis Tikas, were captured and killed by the National Guard; anecdotal evidence suggests that Tikas had been lured out to discuss a truce. As the strikers ran out of ammunition, they retreated from the camp into the surrounding countryside. Women and children, hiding from the bullets that strafed the camp, huddled in cellars that had been dug underneath their tents. In the evening the National Guard troops soaked the tents in kerosene and set them on fire. In one cellar 11 children and 2 women were found burned and suffocated. In all, 25 people were killed during the Ludlow Massacre, 3 of whom were National Guard troops.

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In retaliation for the massacre, miners attacked antiunion town officials, strikebreakers, and the mines, taking control of an area about 50 miles long and 5 miles wide. As many as 50 people died during the reaction to the Ludlow Massacre. Fearing a further escalation of violence, U.S. President Woodrow Wilson sent in federal troops to restore order. Unlike the National Guard, the federal troops were impartial and kept strikebreakers out of the coal mines. The strike ended on December 10, 1914. While the workers got little in the way of tangible benefits from their strike, the UMWA gained 4,000 new members.

Congress held hearings but took no concrete actions. The trials of more than 400 miners dragged on until 1920, but none were convicted. Twelve National Guardsmen were exonerated before a court-martial. Determined to undercut unions and avoid another violent strike, Rockefeller instituted a system of company-sponsored unions as an alternative to the UMWA.