Berlin is in Germany.
The Golden Twenties was a vibrant period in the history of Berlin , Germany , Europe and the world in general . Berlin . Located in northeastern Germany on the banks of the rivers Spree and Havel , it is the centre of the Berlin-Brandenburg Metropolitan Region , which has roughly 6 million residents from more than 180 nations . Berlin in the 1920s was the third largest municipality in the world . Following German reunification in 1990 , Berlin once again became the capital of all-Germany . Nazi Germany is the common English name for the period in German history from 1933 to 1945 , when Germany was governed by a dictatorship under the control of Adolf Hitler and the Nazi Party ( NSDAP ) .