Why were yellow and earth tone the main colors of military uniforms in many countries during World War II, such as the Japanese army, some national armies, the Eighth Route Army, the Soviet Union, Bri

Why were yellow and earth tone the main colors of military uniforms in many countries during World War II, such as the Japanese army, some national armies, the Eighth Route Army, the Soviet Union, Britain and so on? This involves the printing and dyeing industry. In the era when the chemical industry was not so developed, natural dyes were used for dyeing. Each dye corresponds to different natural products, such as conch powder in purple, cinnabar in red, and so on. Comparatively speaking, green is not very expensive, but for the poor, khaki, gray, white and black are easy to dye, and a country with hundreds of thousands of troops has to use cheap ones.

Germany is an exception. In 1950s, when Japan, the Soviet Union and other countries naturally dyed some colors, the Second Reich of Germany completed the research and development of full-color chemical dyes at 1890. For Germany, which basically has no colonies and produces oil and rare metals, light dyes and synthetic rubber contribute more tax revenue each year than France. Isn't that terrible?