I’m not at home or I’d go through my back issues. One of the articles about museum treasures showed what I think was a Turkish arrow (I could be totally wrong about the Turkish part, but it surely was an arrow) with leather fletching.
When you think about the characteristics of thin leather and modern plastic vanes, I don’t suppose it is all that different. For that matter, a lot of people seem to be using duct tape for vanes.
I’ve not tried leather, but I know I like feather fletching better than plastic vanes.
Patrick