This image is a faithful reproduction of a two-dimensional work of art and thus not copyrightable in itself in the U.S. as per Bridgeman Art Library v. Corel Corp.; the same is also true in many other countries, including Germany.
The original two-dimensional work shown in this image is free content because:
This image is now in the public domain because its term of copyright has expired in Japan. According to articles 51 and 57 of the copyright laws of Japan, under the jurisdiction of the Government of Japan all non-photographic works enter the public domain 50 years after the death of the creator (there being multiple creators, the creator who dies last). This applies world-wide.
Note: This template cannot be used for photographs or film.