The flag of Nazi Germany, officially the flag of the German Reich, featured a red background with a black swastika on a white disc. This flag came into use initially as the banner of the Nazi Party (NSDAP) after its foundation. Following the appointment of Adolf Hitler as Chancellor in 1933, this flag was adopted as one of the nation's dual national flags, the other being the black-white-red triband of the German Empire. This dual flag arrangement ended on 15 September 1935, one year after the death of Reich President Paul von Hindenburg, and the Nazi flag became the only national flag of Germany. One reason for the change may have been the "Bremen incident" of 26 July 1935, in which a group of demonstrators in New York City boarded the ocean liner SS Bremen, tore the Nazi Party flag from the jackstaff, and tossed it into the Hudson River. When the German ambassador protested, US officials responded that the German national flag had not been harmed, only a political party symbol. The new flag law was announced at the annual party rally in Nuremberg in 1935, where Hermann Göring claimed the old black-white-red flag, while honoured, was the symbol of a bygone era and under threat of being used by "reactionaries". After rejecting many suggestions and colors, the process of choosing a new flag was described by Hitler as follows: "I myself, meanwhile, after innumerable attempts, had laid down a final form; a flag with a red background, a white disk, and a black swastika in the middle. After long trials I also found a definite proportion between the size of the flag and the size of the white disk, as well as the shape and thickness of the swastika." After Hitler was appointed Chancellor of Germany on 30 January 1933, the black-red-gold tricolour flag was discarded; a ruling on 12 March established two legal national flags: the reintroduced black-white-red imperial tricolour and the flag of the Nazi Party. Nazi ensigns had a through and through image, so the "left-facing" and "right-facing" version were each present on one side.