I was going to update the BRD on this to reflect boundaries immediately before the Gebietsreformen of the 60s and 70s (so roughly 1964), but the German Wikipedia's decision to self-immolate for copyright reform made that a bit difficult. So.
In 1952, the DDR abolished federalism and instituted 12 districts (
Bezirke) to replace its earlier five states. This was the result.
Kreise 1952
These boundaries more or less persisted until the Wende, with a few exceptions:
- In 1967, western sections of Halle (Saale) were split off to form the new city of
Halle-Neustadt, which was supposed to be a prototype of the new socialist city. It was merged back into Halle during the Wende, and today serves as a prototype of the post-communist sinkhole.
- The second constitution, passed in an April 1968 "referendum", integrated East Berlin into the republic as
Berlin, Hauptstadt der DDR, a de facto 13th district.
- Greifswald, which grew fast after the DDR's largest nuclear power station came online in 1974, was split off from its Landkreis and made a separate city at some point in the 70s.
There were also small changes to the Landkreise, but these are, again, inaccessible to me.