In the early 11th century Emperor Henry II entrusted the administration of the Klever Reichswald, a large forested area around the Kaiserpfalz at Nijmegen directly subordinate to the Imperial rule, to local Lower Lorrainian nobles at Geldern and Kleve. A County of Cleves (German: Grafschaft Kleve; Dutch: Graafschap Kleef) was first mentioned in the 11th century. Dietrich I was the first Count of Cleves and reigned from 1092 through 1119. In 1283, Cleves fought in the War of the Limburg Succession and helped weaken the powerful Electorate of Cologne. In 1355 Zevenaar passed from the control of the Duchy of Guelders to the County of Cleves.
The Cleves-Mark territories became one of the most significant estates of the Lower Rhenish–Westphalian Circle in 1500, rivaled by the Prince-Bishops of Münster. In 1511 John III of La Marck, son of Duke John II of Cleves, married Maria and her estates and titles were then merged with the Duchy of Cleves. Upon the death of his father-in-law Duke William IV, John inherited the fiefs of Jülich and Berg through his wife. When John III succeeded his father as Duke of Cleves in 1521, the states of Jülich, Berge, Cleves and Mark formed the United Duchies of Jülich-Cleves-Berg.[1] His daughter Anne of Cleves (1515–1557) even became Queen Consort of England for a few months in 1540, as her brother William, duke since 1539, quarreled with Emperor Charles V over the possession of Guelders and sought support from King Henry VIII.[2]
The House of Cleves considers itself to be descended from Rutger von Antoing, a Flemish nobleman. He was enfeoffed of imperial property near Kleve in 1020, and Tomburg Castle some time after. The first documented lord from the House of Cleves is Dietrich, numbered variously as II or III, in 1092.[6]
^Hayden, J. Michael (1973). "Continuity in the France of Henry IV and Louis XIII: French Foreign Policy, 1598-1615". Journal of Modern History. 45 (1): 22. doi:10.1086/240888. S2CID144914347.
^Romeyk, Horst (1985). Verwaltungs- und Behördengeschichte der Rheinprovinz 1914–1945 [History of Administration and Public Authorities of the Rhine Province 1914–1945] (in German). Düsseldorf: Droste Verlag. pp. 123 ff.
^Miller, Clarence H. (March 1994). "Thomas More's Letters to Frans van Cranevelt, including Seven Recently Discovered Autographs: Latin Text, English Translation, and Facsimiles of the Originals". Moreana. 31 (Number 117) (1): 65. doi:10.3366/more.1994.31.1.4.