In the movie Giovanni's Island, Junpei and Kanta's Grandfather say to one of the women of the household:
There's no telling what they'll do to the womenfolk if you don't hide. You better paint your faces black to like men.
Why would painting their faces black have made them look like men? Would the logic behind this have been that they would have looked tanned, and thus possibly misconstrued, by the occupying Americans, as outdoor laborers which at that time would have predominantly consisted of men?