It consisted of the 1934-established Mecklenburg (a merger by the Nazi Gauleiter Friedrich Hildebrandt of the free states of Mecklenburg-Schwerin and Mecklenburg-Strelitz) and parts of the former Prussian provinces of Pommern (Western Pomerania to the Oder–Neisse line) and Hanover (Amt Neuhaus).

[1] From 1947, the term Vorpommern was excluded from the official name as the SMAD feared that this would support revisionist actions against formerly German parts of Poland (in particular Farther Pomerania).

As the ruling communists aimed to build a quasi-unitary state, Mecklenburg was in effect dissolved by a change of the Constitution of East Germany in July 1952.

The abolition of the Chamber of States in 1958 and the ratification of two new constitutions in 1968 and 1974 respectively finally eliminated all forms of federalism in East Germany until the peaceful revolution in 1989.

After the first free elections in East Germany, the Ländereinführungsgesetz (State Establishment Act), adopted on 22 July 1990 by the Volkskammer, recreated the Länder in the German Democratic Republic that had been abolished in 1952.

However, since changes to the boundaries of municipal districts were not reversed, and also due to considerations of expediency, these new Länder were formed by merging the Kreise of East Germany.