Cleves, duchy of
duchy of Cleves, former state, W Germany, on both sides of the lower Rhine, bordering on the Netherlands. Cleves was the capital. A county from late Carolingian times, it acquired (late 14th cent.) the county of Mark, in Westphalia, and in 1417 was made a duchy. In 1521, Duke John III of Cleves inherited through marriage the duchies of Jülich and Berg and the county of Ravensberg. His daughter, Anne of Cleves, was married in 1540 to Henry VIII of England. In 1609 the male line became extinct, and a complicated dynastic quarrel for the succession followed. Brandenburg acquired (1614) Cleves, Mark, and Ravensberg; the Palatinate-Neuburg line of the Bavarian house of Wittelsbach took Jülich and Berg. The succession was not finally settled until 1666, when the Treaty of Cleves confirmed the division. Cleves was held by France during the French Revolutionary Wars and in 1815 was returned to Prussia.