The area that is now the City of Duquesne was originally part of Mifflin Township, Allegheny County, which covered much of the area south of the Monongahela River. The city has often been described as a "steel town," and in fact the steel mill pre-dated the city itself. Construction on the steel plant began on May 28, 1885, and by the spring of 1886, the Duquesne Steel Company was producing steel. In 1888, Allegheny Bessemer Steel Company purchased the mill, but the plant was dealt a blow when the workers went on strike in April 1889. The plant was shut down for more than five months and was on the verge of closing for good when it was purchased by the Carnegie Steel Company.
With the advent of the mills came an influx of people into what was still largely a rural area. The population rapidly increased in 1891 and the decision was made to incorporate Duquesne as a city. This was accomplished in September of that year and the first election was held in February 1892. By 1916 the population had expanded to 19,000 people, making Duquesne the fourth largest in Allegheny County.
The premier amenity of the city at this time was the Carnegie Library, the third built in the Monongahela valley, and one of hundreds to be built around the country from money provided by Andrew Carnegie. The $300,000 library was a huge structure that also housed a gymnasium with an Olympic-size swimming pool and a music hall. It was torn down in 1968 because it had become too expensive to operate.
As the steel business boomed during and after World War I, so did Duquesne's population. It eventually reached its peak of 21,396 in 1930. During the Depression, the population dropped slightly, but by 1950, it was still over 17,000. About 16 percent of the population were foreign-born residents, reflecting the large number of immigrants who flocked to the mill town. Success of the city was generated by the success of its steel mills. In 1948, the Carnegie-Illinois Steel Corporation employed over 8,000 people at its Duquesne Works.
Unfortunately, the fortunes of the city remained closely tied to those of the Duquesne Works through the latter half of the twentieth century. The mill began a slow descent in work force and production in the 1960s that became a rapid slide in the 1970s. After nearly a century of service, the mill closed its doors for good in 1980, throwing the city's economy into a tailspin from which it has yet to fully recover. The people of the city would have to learn to live without the mill that had forged its very existence.
In recent years, the City of Duquesne has continued to reshape itself by embarking upon many positive initiatives. The Regional Industrial Development Corporation bought the mill site and began the process of demolishing many of the buildings, cleaning up environmental hazards and enticing new firms into the site.