what do the colors of germany flag mean
The black-red-gold flag was used to symbolize the movement against the Conservative European Order that was established after Napoleon's defeat.
Flag of Germany
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.

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Flag of Germany [SEP] Origins
Another claim goes back to the uniforms (mainly black with red facings and gold buttons) of the Lützow Free Corps, comprising mostly university students and formed during the struggle against the occupying forces of Napoleon. Whatever the true explanation, these colours soon came to be regarded as the national colours of Germany during this brief period, and especially after their reintroduction during the Weimar period, they have become synonymous with liberalism in general. The colours also appear in the medieval .