Freistaat Bayern

Source: Wiki commons                                                                  

Bavaria.  The Kingdom of Bavaria, once an independent country, was incorporated into the German Empire in 1871 after the victory in the Franco-Prussian war.  The Kingdom continued in existence under the long-ruling Wittelsbach dynasty, and was permitted, among other things, to issue its own postage stamps.

With the defeat of Germany in 1918, Bavaria ceased to be a monarchy.  Several rival successor regimes then struggled for control.  Freistaat Bayern was the name of one of those rival governments.

Freistaat Bayern exists solely as an overprint on stamps of Germany and the Kingdom of Bavaria.