Patriotic resistance. The Lützow Free Corps, composed of volunteer German students and academics fighting against Napoleon in 1813, could not afford to make special uniforms and therefore adopted black, as the only color that could be used to dye their civilian clothing without the original color showing. In 1815 the students began to carry a red, black and gold flag, which they believed (incorrectly) had been the colors of the Holy Roman Empire (the imperial flag had actually been gold and black). In 1848, this banner became the flag of the German confederation. In 1866, Prussia unified Germany under its rule, and imposed the red, white and black of its own flag, which remained the colors of the German flag until the end of the Second World War. In 1949 the Federal Republic of Germany returned to the original flag and colors of the students and professors of 1815, which is the flag of Germany today.