Anhalt-Dessau was a principality and later a duchy located in Germany. It was created in 1396 following the partition of the Principality of Anhalt-Zerbst. The capital of the state was Dessau. Anhalt-Dessau experienced a number of partitions throughout its existence with Anhalt-Köthen being created in 1471. The principality was partitioned for a second time in 1544 with Anhalt-Zerbst and Anhalt-Plötzkau being created. From 1561 until 1603 Anhalt-Dessau was under the rule of the Prince of Anhalt-Zerbst, and in 1603 Anhalt-Dessau was recreated, being raised to a duchy in 1807.
Anhalt-Köthen became extinct on the death of the Duke of Anhalt-Kothen, 23 November 1847, its territories were united to Anhalt-Dessau by Patent of 22 May 1853. Following the death of the last Duke of Anhalt-Bernburg on 19 August 1863, all of the Anhalt lands came under the rule of the Duke of Anhalt-Dessau who then took the new title of Duke of Anhalt for the newly created Duchy of Anhalt.