Plötzkau, now a small town to the southwest of Bernburg, was capital of an old county in the marcher region on the edge of the Duchy of Saxony. Its Counts in the 12th century claimed to be Margraves of the Nordmark, though they failed to establish themselves. They died out in the mid-12th century, and Plötzkau became part of of the lands of Albert the Bear, Margrave of Brandenburg and Count of Anhalt. Some of the junior Anhalt princes in the 16th century held Plötzkau. In the partition of 1603 the third brother became Prince of Anhalt-Plötzkau, but when Köthen became vacant in 1665, this line transferred there and gave up Plötzkau to the Prince of Anhalt-Bernburg.