<P> After the Austro - Prussian War in 1866, the Prussian - dominated North German Confederation adopted a tricolour of black - white - red as its flag . This flag later became the flag of the German Empire, formed following the unification of Germany under the Prussian king who became emperor in 1871, and was used until 1918 with the end of the First World War . Black, white, and red were reintroduced as the German national colours with the establishment of Nazi Germany under Adolf Hitler in 1933, replacing German republican colours with imperial colours until the end of World War II . </P> <P> The colours of the modern flag are associated with the republican democracy first proposed in 1848, formed after World War I, and represent German unity and freedom . During the Weimar Republic, the black - red - gold colours were the colours of the democratic, centrist, and republican political parties, as seen in the name of Reichsbanner Schwarz - Rot - Gold, formed by members of the Social Democratic, the Centre, and the Democratic parties to defend the republic against extremists on the right and left . </P> <P> The German association with the colours black, red, and gold surfaced in the radical 1840s, when the black - red - gold flag was used to symbolize the movement against the Conservative European Order that was established after Napoleon's defeat . </P> <P> The Frankfurt Parliament had declared the black - red - gold as the official colours of the German Confederation, with the red in the tricolour most likely referencing the Hanseatic League, and the gold and black symbolizing Austria as its empire, considered to be "German", had an influence over (what would become) southern Germany . The Flags of the Holy Roman Empire was just black and gold . </P>

What does the red on the german flag represent