Charleroi (shärlərwäˈ) [key], city (1991 pop. 206,214), Hainaut prov., S Belgium, on the Sambre River and on the Charleroi-Brussels Canal. It is a commercial and industrial center and a rail junction. Manufactures include steel, glass, machinery, processed food, and chemicals. Charleroi was founded in 1666 and named for Charles II of Spain. It was of strategic importance in the wars of the 17th and 18th cent. The Germans won a battle there (1914) in World War I. It is noted for its modern public buildings, such as the town hall (1936), and is the seat of a technical university.