The Colorado Fuel and Iron Company (CF&I) was a large steel conglomerate founded by the merger of previous business interests in 1892.

The first, and only until World War II, integrated iron and steel mill west of St. Louis was built in 1881 in Pueblo on the south side of the Arkansas River by the Colorado Coal and Iron Company (CC&L), an affiliate of the narrow-gauge Denver and Rio Grande Railway Company (D&RG), controlled by General William Jackson Palmer and Dr. William Abraham Bell.

[6][7] Local resources included water from the Arkansas River, coal from Trinidad, limestone from a few miles south of Pueblo, and iron ore from the San Luis Valley with rail transportation provided by the D&RG.

[8][9] The original steel works were one of the projects of the Central Colorado Improvement Company, founded by General William J. Palmer in 1872, with plans "to purchase lands, minerals springs, coal and iron and other mines and quarries in Colorado Territory, and the establishment and building up of colonies, towns, coal mining, iron making and manufacturing works, and to build canals and wagon roads.

[8][11] A neighborhood of makeshift homes arose near the works, initially called Taylorville, then Steelworks, then, as more permanent dwellings were constructed, Bessemer in 1881.

The company turned to production of coke and coal opening additional mines near Trinidad and others near Canon City, Walsenburg, and Crested Butte.

On Osgood's initiative these two companies merged in 1892 to form Colorado Fuel and Iron with members of the Iowa Group in control.

[1] Often idle during the decades of the 1880s and 1890s due to stiff competition and the effects of the panic of 1893, the steel mill at Pueblo was small and obsolete.

[14] Deeper ores from Calumet contained greater quantities of silicon, which interfered with the iron making process.

Calumet was closed in 1899 and production shifted to the Sunrise Mine near Hartville, Wyoming about 100 miles north of Cheyenne which the company had leased in 1898.

The Sociological Department began to set standards for education by regulating the curriculum and getting miners' children involved.

Through the Kindergarten program, children were taught English and the importance of industrial labor in hopes of making them good future employees.

[22] Also part of the multi-pronged efforts to promote support for the Company in the latter-half of 1914, several schools were constructed, including one in Primero.

The main blast furnace structures were torn down in 1989, but due to asbestos content many of the adjacent stoves and support buildings still remain.

In 1902, facing cash flow problems, Osgood turned to George Jay Gould a principal stockholder of the Denver and Rio Grande for a loan.

[29] In 1904 the assets of the firm and its subsidiaries were consolidated as Colorado Industrial Company whose stock was wholly owned by the shareholders of CF&I, mainly Gould and Rockefeller.

The strike, which lasted 11 months, produced no gains and demoralized the miners, was fought vigorously with strikebreakers and reduced steel production.

[31] Following the strike substantial investments were made to the mill including purchase of water rights in the Arkansas River and a reservoir at the site of Sugar Loaf Dam west of Leadville.

Previously the mill had relied on the scant and variable flow of the St. Charles River, storing water in Lake Minnequa.

[31] Gates, Rockefeller's financial advisor, had little confidence in Jesse Floyd Welborn who had been elected by Gould and his allies to succeed Hearne as manager in 1907.

When Gould suffered severe financial losses due to the Panic of 1907 his need for funds resulted in transfer of his interests to Rockefeller.

[33] Greater profits proved elusive, however, due to eastern competition and limited transportation facilities such as a perennial shortage of railway cars to ship coal.

[36] Evidence from CF&I's archives reveals that the company infiltrated, propagandized against, and attempted to disrupt the Industrial Workers of the World.

Although experienced miners from Cornwall were encouraged to immigrate and were taken on particularly at the Sunrise Mine, much of the workforce was inexperienced and not fluent in English.

[37] Lamont M. Bowers, effectively the chief executive officer of CF&I, in addition to his paternalistic concern regarding vices such as drinking, gambling, and prostitution which might affect the health of CF&I workers, and also company profits, and his efforts to clean up the mining towns and support enactment of prohibition in Colorado, was strongly anti-union and refused to recognize or negotiate with the United Mine Workers during the period leading up to the major strike of 1913–14.

After the violence in the Spring of 1914, United States Secretary of Labor William Bauchop Wilson attempted mediation.

[39] The casualties suffered at Ludlow were successfully labeled a massacre and mobilized public opinion against the Rockefellers and the coal industry.

[39] In October, 1915 John D. Rockefeller Jr. with the assistance of William Lyon Mackenzie King, director of the Rockefeller Foundation and head of its Department of Industrial Research, introduced the Colorado Industrial Plan, an internal system of worker representation which included guarantees of basic decency in working conditions and in company towns.

The old CF&I facility, under new ownership, hired permanent replacement workers, leading to further tension between the new employer and the union.

Currently, one EAF is used at the facility to convert over a million tons of scrap per year into steel billets of various sizes.