Industrialist Ernest T. Weir (1875-1957), who was born in Pittsburgh and died there, founded Phillips Sheet & Tin Plate in Clarksburg, West Virginia, in 1905 with J. A. Phillips. After the death of Phillips, Weir moved the company to a farm just north of the village of Hollidays Cove in southern Hancock County, the site of present Weirton. On August 1, 1918, Weir's 43rd birthday, the company was renamed Weirton Steel Company.

Weir created an integrated steel mill that became West Virginia's largest employer, the state's largest taxpayer, and the world's largest tin plate producer. He created a town around his mill, and for years his Weirton Improvement Company provided Weirton's sewers, water service, garbage pickup, and other municipal services. In 1927, he took over as the chief executive officer of National Steel, of which Weirton Steel formed the keystone. In the 1930s, Weir defied Franklin Roosevelt's National Recovery Administration and National Labor Relations Board and kept national unions from organizing his mills.

Weirton Steel joined in the national recovery following the Great Depression Depression. It converted to wartime production during World War II, producing howitzer shells and other munitions and contributing to the atom bomb project. The company shared the steel industry prosperity of the post-war years, but began to suffer the effects of foreign competition by the 1960s. Weirton modernized production during the decade but lagged behind European and Japanese producers in this regard.

During the 1970s, the American steel industry fell upon depressed times. On March 2, 1982, National Steel announced that subsidiary Weirton Steel would close unless a buyer came forward. When no corporate buyer materialized, Weirton steelworkers undertook a campaign to purchase the plant under an Employee Stock Ownership Plan or ESOP. Various constituent groups, political leaders, management, and labor joined in the innovative effort.

A plan was developed by which Weirton Steel bought the plant and its raw materials and inventory from National Steel. In September 1983, Weirton's workers approved the deal by a margin of seven to one, and in January 1984 ownership was transferred to the employees. Under the plan, the workers gave back 32 percent of their wages. All pensions before 1982 remained the responsibility of National; all property reverted to Weirton; and National was to receive $66 million over 15 years. What was lost in the wage giveback was later made up in profit-sharing for workers.

The rest of the 1980s were profitable years for the ESOP, and employees reaped many financial benefits. In 1989, to raise more money for continued capital improvements, Weirton Steel stock began trading on the New York Stock Exchange, despite the strident objections of many ESOP members.

Making the company public did not improve the company's bottom line, and throughout the 1990s, employment continued to fall as overseas competition adversely affected all American steel companies. Although the Weirton ESOP remained the largest of its kind in the United States, employment hit a 70-year low as the 21st century began.

In 2003, despite remaining the fifth-largest private employer in West Virginia, Weirton Steel entered bankruptcy. The plant was purchased by International Steel Group (ISG) in 2004 and then sold a year later to Mittal Steel—now ArcelorMittal. Under ArcelorMittal Weirton, which later became a subsidiary of Cleveland-Cliffs Inc., employment steadily declined. Even so, the site retained its distinction as the world’s largest tin plate producer, despite lacking hot metal operations. Instead, the remaining facilities processed coils shipped from the corporation’s other U.S. plants, cleaning and coating them for use.

In the early 2020s, Cleveland-Cliffs invested roughly $50 million into the Weirton facility, and by 2022, it ranked as West Virginia’s 51st-largest private employer.

That stability proved short-lived. In May 2023, citing competition from underpriced imports, Cleveland-Cliffs announced layoffs of approximately 300 workers—about one-third of its local workforce. Then, in February 2024, the company revealed plans to close the plant entirely the following April, affecting roughly 900 employees. The announcement came just one week after the International Trade Commission lifted a year-old tariff on tin- and chromium-coated steel imports from Canada, China, Germany, and South Korea. The commission concluded that these imports, often criticized as “dumped” at below-market prices, had minimal financial impact on U.S. producers.

Meanwhile, much of the former steel complex has been dismantled. Key structures—including the open hearth, blooming mill, quality control lab, and research and development facilities—have been demolished. A site on Weirton Heights was cleared for a new Walmart, which has since become one of the region’s largest private employers.

In July 2024, Cleveland-Cliffs announced plans to construct an electrical distribution transformer manufacturing plant in Weirton—an investment tied to the growing need to modernize the nation’s power grid. However, this project was scrapped in 2025.

Meanwhile, new development efforts signal a potential economic transition. In December 2022, the state of West Virginia announced a partnership with Form Energy to build a 55-acre iron-air battery factory on part of the former Weirton Steel property. The $760 million project broke ground in May 2023 and currently employs nearly 400. Employment is expected to almost double by 2028.