The economy of Youngstown, Ohio, United States, flourished in the 19th and early 20th centuries, with steel production reaching all-time highs at that time. The steel boom led to an influx of immigrants to the area looking for work, as well as construction of skyscrapers in the area. The city's population peaked at 170,002 in 1930, just at the onset of the Great Depression. World War II also brought a great demand for steel. After World War II, demand for steel dropped off dramatically, and industrial base of Youngstown began to see a decline.
Youngstown's economy has been impacted by a loss of the steel industry jobs which started on September 19, 1977, on what became known to locals as "Black Monday", and continued into the mid-1980s. While the loss of steel industry jobs in the region coincided with the general deindustrialization of Rust Belt cities such as Youngstown as well as the United States as a whole, Youngstown's economic struggles have been well documented. In the Mahoning Valley, where Youngstown is located, the population was halved, while non-industrial businesses were forced to close or relocate due to cascading effects resulting from Youngstown's deindustrialization.