Hamm (häm) [key], city (1994 pop. 182,390), North Rhine–Westphalia, W Germany, on the Lippe River, in the Ruhr district. The city contains iron and steel foundries and manufactures textiles and machinery, as well as wire and cable. Founded in 1226, Hamm was the capital of the county of Mark until 1809. An active member of the Hanseatic League, it passed to Cleves in the 14th cent. and later (1614) to Brandenburg. The city was badly damaged in World War II, in a bombing that destroyed over half of the buildings.