The introduction of primogeniture in Anhalt-Dessau in 1727 left Dietrich without any chance to take part in the government of Dessau. Because his oldest brother, the Hereditary Prince William Gustav, had already died before his father, the second brother, Leopold Maximilian, inherited the princely title and government. After the latter's death in 1751, the succession passed to his eleven-year-old son Leopold Frederick Franz. Dietrich acted as regent of Anhalt-Dessau on behalf of his nephew until 1758, when Leopold Frederick Franz was proclaimed an adult and assumed the government of his principality.
Dietrich never married or had children. Later, his palace in Dessau was used by a progressive school, "The Philanthropinum".
References
^Anton Balthasar König, Henning Alexander von Kleist, Biographisches Lexikon aller Helden und Militärpersonen: T. G-L, A. Wever, 1789, pp. 275–276.