The Midvale Steel Company manufactured steel parts for the railroad industry and the armaments industry. The company was known for casting, forging, and machining high-quality steels, including alloy steels.

Immediately following the Civil War, several Philadelphia businessmen established a steelworks in the Nicetown area of Germantown. In 1872 it became known as the Midvale Steel Works, with the famous engineer William Sellers (1824-1905) as president. Its major products were railroad wheels cast from open-hearth steel, one of the earliest uses of this type of steel in the United States. Midvale Steel was notable also for its early experimentation with alloy steels, producing specialty products used in both the Eads Bridge in St. Louis and the Brooklyn Bridge. Frederick W. Taylor (1856-1915), famous efficiency expert, spent much of his early career at Midvale, becoming their chief engineer before leaving to work for the Bethlehem Steel Company.

The name was changed to the Midvale Steel Company in 1880. In 1895 Midvale began the manufacture of ordnance, including large naval guns and shells, and in 1900 they started making marine engines. With the rapid expansion brought about by World War I the company became the Midvale Steel and Ordnance Company in 1915, with plants in Johnstown and Coatesville, Pennsylvania, as well as the original works in Philadelphia. In 1917 Midvale ranked among the top twenty American corporations in revenue, but in 1923 all the company's properties except the Philadelphia works were acquired by the Bethlehem Steel Company. The one remaining plant in Nicetown was operated as the Midvale Company from then on.