At this location, striking miners set up a tent colony in September of 1913. Tensions built in the ensuing months between the miners and their union (the United Mine Workers of America- UMWA) and the mine owners- the Rockefeller family-owned Colorado Fuel & Iron Company (CF&I), the Rocky Mountain Fuel Company (RMF), and the Victor-American Fuel Company (VAF).
On April 20, 1913, the 1,200 striking miners and their families were attacked by the Colorado National Guard and Colorado Fuel & Iron Company camp guards. In the ensuing battle, between 19 and 25 people were killed. The sources vary on the exact number, but all sources include two women and eleven children, asphyxiated and burned to death under a single tent.
The "Ludlow Massacre" became a rallying cry and 700 to 1,000 striking miners "attacked mine after mine, driving off or killing the guards and setting fire to the buildings."
By the time the federal troops stopped fighting, the death toll was between 69-199 people.
