The Imperial County of Rantzau was an immediate state of the Holy Roman Empire which lasted from 1650 to 1864. Its territory is more or less congruent with the present Amt Rantzau.

History

In 1649, Frederick III, Duke of Holstein-Gottorp, sold his part of the Lordship of Pinneberg, which had formerly belonged to the County of Schauenburg, to Count Christian zu Rantzau (1614–1663), royal Danish governor of Holstein. In 1650 or 1651, Rantzau became an immediate county and state of the Holy Roman Empire. In 1726, it was annexed by the Danish rulers, after Wilhelm Adolf, Count of Rantzau (1688-1734), had murdered his brothers and was imprisoned. Wilhelm Adolf died in 1734 and Rantzau was inherited by the Duchy of Holstein, which was reigned by the Danish kings and its secundogenitures.

Origin in the House of Holstein