Kleve

The first comital house of Cleves sprang from the Lower Rhine nobility. Around 1020 Emperor Henry II enfeoffed the brothers Gerhard and Rutger Flamens; Gerhard founded the Guelders line, while Rutger's descendants became counts of Cleves, first styling themselves after Kleve Castle in 1092. Their seat was the Schwanenburg, and later legend traced the family to a swan knight.

The county grew between Cleves and Kalkar; its counts founded the collegiate churches of Wissel and Bedburg. In 1283 Cleves joined the War of the Limburg Succession against Cologne, gaining Zevenaar from Guelders in 1355.

When Count John died without a male heir in 1368, the county passed to his nephew Adolf III of the Marck. From 1391 Cleves and the Marck were ruled in personal union by the House of La Marck, whose head became Duke of Cleves in 1417.