American corporation first incorporated on Dec. 10, 1904, for the purpose of consolidating Bethlehem Steel Company (of Pennsylvania), the Union Iron Works (with shipbuilding facilities in San Francisco), and a few other smaller companies. The corporation was newly incorporated on July 1, 1919. Headquarters are in Bethlehem, Pa.

The company's history traces to 1857, when a group of railroaders and investors of the city of Bethlehem founded the Saucona Iron Company, which four years later was renamed Bethlehem Iron Company; the works was designed principally to turn out wrought-iron railroad rails. In 1899 the facilities were acquired by a newly formed enterprise, the Bethlehem Steel Company.

The major founder of the corporation in 1904–05 was Charles M. Schwab (Schwab, Charles M), who had earlier been one of the major figures in the creation of United States Steel Corporation (1901). In August 1901 he had bought control of Bethlehem Steel Company, only to see it fail in a financial scandal. Schwab borrowed and invested heavily to save the company's assets, absorb other companies, and launch the Bethlehem Steel Corporation. The corporation thrived, partly as a result of the expanding orders for guns, munitions, and naval vessels from European powers both before and during World War I. In the first four decades of its existence, the corporation absorbed a number of iron-ore, coal, and steel-producing properties from coast to coast. During World War II and the postwar years, it continued to expand. Like other U.S. steel companies, Bethlehem began to diversify during the 1970s in the face of strong competition from foreign steelmaking companies; its other activities include the production of plastics and related chemical products and the mining of nonferrous ores.