The Colorado Fuel and Iron Company was enormously important to the industrialization of the West. Its roots dated to 1872, when General William Jackson Palmer and his colleagues in the Denver and Rio Grande Railway sought a local source for steel rails for their expanding narrow gauge empire. It became the first vertically integrated steel mill west of the Mississippi River, owning and controlling as many parts of its operation as possible, from raw materials, production, transportation, and marketing to distribution. Across Colorado, New Mexico, Oklahoma, Utah, and Wyoming, it owned more than 60 mines and quarries that supplied coal, iron ore, limestone, calcite, dolomite, and fluorspar. At the steel mill, these resources were washed, heated, coked, refined, and rolled into products such as rails, seamless tubes, wire, rods, and bars for national and international customers. At its peak in the 1950s, the company employed more than 12,000 workers in steelmaking and another 10,000 in administrative, mining, and support work, and for many years it was the state's largest private employer. The promise of work in its mines and mills drew Italians, Croatians, Slovenians, Mexicans, Germans, Greeks, Japanese, Hispanic-Americans, African-Americans, and many others to its coal camps and company towns, where families lived in company houses, shopped at the Colorado Supply Company store, attended company-built schools, and received care from company doctors. It remained the Rocky Mountain region's chief heavy industry until the defense industry expanded into California during World War II. It did not survive the collapse of the steel market in the 1980s, declared bankruptcy in November 1990, was purchased by Oregon Steel in 1993, and today is operated by EVRAZ Rocky Mountain Steel.