Colorado Coalfield War

The Colorado Coalfield War was a major labor uprising in the southern and central Colorado Front Range between September 1913 and December 1914. Striking began in late summer 1913, organized by the United Mine Workers of America (UMWA) against the Rockefeller-owned Colorado Fuel and Iron (CF&I) after years of deadly working conditions and low pay. The strike was marred by both targeted and indiscriminate attacks from both strikers and individuals hired by CF&I to defend its property. Fighting was focused in the southern coal-mining counties of Las Animas and Huerfano, where the Colorado and Southern railroad passed through Trinidad and Walsenburg. It followed the 1912 Northern Colorado Coalfield Strikes.

Tensions climaxed at the Ludlow Colony, a tent city occupied by about 1,200 striking coal miners and their families, in the Ludlow Massacre on 20 April 1914 when the Colorado National Guard attacked. In retaliation, armed miners attacked dozens of mines and other targets over the next ten days, killing strikebreakers, destroying property, and engaging in several skirmishes with the National Guard along a 225-mile (362 km) front from Trinidad to Louisville, north of Denver. Violence largely ended following the arrival of federal soldiers in late April 1914, but the strike did not end until December 1914. No concessions were made to the strikers. An estimated 69 to 199 people died during the strike, though the total dead counted in official local government records and contemporary news reports is far lower. The labor dispute was the bloodiest in the United States and Colorado historian William J. Convery called it the "bloodiest civil insurrection in American history since the Civil War." The Colorado Coalfield War is notable for the number of company-aligned dead in a period when strikebreaking violence typically saw fatalities exclusively among strikers, and contributed to the rapid escalation of violence in the later Battle of Blair Mountain.