:::It is exacly the same German state since 1867, beginning with the North German Confederation (1866 it was only a confederation, but in 1867 it became a state by a constitution!). At that time a few years later, in 1871, the southern German states like Bavaria or Wurttemberg did exactly the same like the GDR did in 1990: they acceded to the German federation to form the whole German nation-state: Germany. 
 :::The only difference between 1871 and 1990 is, that in 1990 the GDR was already [and everytime since 1949] part of the German nation, simly known as "Germany as a whole".