Flag of Germany
While the use of black-red-gold had been suggested in the Soviet zone in 1946, the Second People's Congress in 1948 decided to adopt the old black-white-red tricolour as a national flag for East Germany. This choice was based on the use of these colours by the National Committee for a Free Germany, a German anti-Nazi organisation that operated in the Soviet Union in the last two years of the war. In 1949, following a suggestion from Friedrich Ebert, Jr., the black-red-gold tricolour was instead selected as the flag of the German Democratic Republic upon the formation of this state on 7 October 1949. From 1949 to 1959, the flags of both West and East Germany were identical. On 1 October 1959, the East German government changed its flag with the addition of its coat of arms. In West Germany, these changes were seen as a deliberate attempt to divide the two Germanys. Displaying this flag in West Germany and West Berlin—where it became known as the (divider-flag)—was seen as a breach of the constitution and subsequently banned until the late 1960s.
Reichskriegsflagge
Because Prussia had emerged as the leading German state and the black-red-golden colour scheme was, at that time, associated with pan-Germanism (a Germany including Austria) and the revolution of 1848, the Prussian King and President of the North German Confederation, Wilhelm I, insisted on using new flags inspired by Prussia and without the traditional German colours. Therefore, the North German and eventually Imperial German flags prominently featured the Prussian colours (black and white) as well as symbols like the Prussian eagle and the Iron Cross. And while seafaring was the traditional domain of the Hanse in Germany, virtually all of the 19th century German coastline (including the North Sea coast) and naval power belonged to Prussia after the decisive victory in 1866.