Frank J. Hayes (May 4, 1882 – June 10, 1948) was an American miner and president of the United Mine Workers of America (UMWA) from 1917 to 1919. A Democrat, he also served as Lieutenant Governor of Colorado in 1937–39. He was born in the coal mining town of What Cheer, Iowa, in 1882, but moved with his family as a boy to Illinois. At the age of 13, he began working in the coal mines. His father was active in the unions. UMWA involvement 1904–1919 He joined the United Mine Workers and held a number of local union offices before being elected secretary-treasurer of District 13 in 1904. A socialist, he allied himself with the radical left-wing of the miners' union and agitated for greater militancy and adoption of socialism as the union's only economic and political philosophy. He was elected an international vice president in 1911. While a vice president, he helped strategize and organize the Paint Creek–Cabin Creek strike of 1912 in West Virginia and the Colorado Coal Strike of 1913–1914 (during which the Ludlow Massacre occurred). Paint Creek-Cabin Creek strike of 1912 The Paint Creek Miners' Union with the help of Hayes, serving as the UMWA International Vice President, declared a strike with eight demands. After the demands were known the Cabin Creek Miners' Union joined the striking miners as well. During the first month of the strike the UMWA organizers kept peace, but subsequently the mine operators hired the Baldwin–Felts Detective Agency to break the strike. After 300 Baldwin-Felts Detectives arrived, the labor organizer Mother Jones also arrived and was subsequently arrested. The strike lasted from April 18, 1912 through July 1913. After the confrontation, Fred Stanton, a banker, estimated that the strike and ensuing armed conflict cost $100,000,000. The confrontation directly caused perhaps fifty violent deaths, as well as many more deaths caused indirectly by starvation and malnutrition among the striking miners. In the number of casualties, it counts among the worst conflicts in American labor union history. Ludlow Massacre The Ludlow Massacre was an attack by the Colorado National Guard and Colorado Fuel and Iron Company guards on a tent colony of 1,200 coal miners and their families at Ludlow, Colorado, on April 20, 1914. About two dozen people, including miners' wives and children, were killed. The chief owner of the mine, John D. Rockefeller Jr., was widely criticized for the incident. The