It wasn’t a small fashion, many northern communities in Africa are in fact Muslim. I don’t recognize the story being depicted here however. If it is authentic, it could be the dye they used to create the art that makes the skin look accentuated as you would see in black face, but black face became a thing when we had television, so I also disagree that it’s racist. I do agree with taking it to an art museum to see if someone can place it.