Mine is this little tidbit about Khaki’s from https://www.heddels.com/2019/05/history-khaki-anything-drab/
“Tried and tested by all the major powers, khaki-dyed, lightweight cotton twills became the de facto uniform for any colonizing power. If you were going to ship your boys abroad to pillage and conquer someplace in the Southern Hemisphere, khaki was your go-to color.”
It was actually rather successful! The paper is available in full here, and there’s a good Tom Scott video on the experiment as well.