In September 1913, the United Mine Workers of America (UMWA) called for a strike against coal mining companies in Colorado, primarily over complaints about poor pay and unsafe working conditions. Miners had long been struggling under the oppressive practices of mine operators, who frequently employed tactics such as wage cuts and unjust dismissals, while workers faced hazardous conditions with little to no protections. The strike drew a large number of miners and their families into a collective movement aimed at securing basic rights and fair labor practices. The UMWA organized rallies and sought to unify miners across the region, encouraging them to withhold their labor until demands were met.

As tensions rose, the situation quickly escalated. Mining companies, seeking to maintain coal production, responded by hiring strikebreakers and employing private security forces to intimidate and suppress the striking miners. This led to violent confrontations at various sites, notably the Ludlow Massacre, where striking miners set up a tent colony in Ludlow, Colorado, only to be met with armed attacks by law enforcement and militia. The violence resulted in several deaths, including miners and their families. This brutal conflict continued for months, drawing national attention and highlighting the severe labor abuses in the mining industry.

The Colorado Coalfield War became a significant chapter in the labor movement, reflecting the intense struggles over workers' rights and economic justice during a period of rapid industrialization and labor unrest in America. The strikers' fight for their rights would eventually lead to important changes in labor laws and safety regulations in the coal mining industry.