Does anyone know what this is?

I found it today nailed to the inside of a closet wall which is an outside wall of the house. Attached in such a way that it couldn't possibly have been put there after the house was built in 1873.

It looks like Japanese print and seems to be wrapped and stuck into a sort of envelope. It was hanging vertically from the top beam and had been there for a very long time. As you can tell from the degradation.

But what in the world is it?

#mystery