City (pop., 2002 est.: 478,600), North Rhine-Westphalia state, western Germany. It lies at the junction of the Rhine and Ruhr rivers and is connected with the North Sea ports by the Rhine-Herne Canal. Known to the Romans as Castrum Deutonis, it was mentioned in AD 740 as Diuspargum, a seat of the Frankish kings. It passed to Cleves in 1290 and, with Cleves, to Brandenburg in 1614. After suffering heavily in the Thirty Years' War, it revived as the seat of a Protestant university from 1655 to 1818. With increasing industrialization after 1880, it is now one of the world's largest inland ports