1 Yen banknote First Issue Series, specifically issued during WWII 1943

Design and Features:
Obverse: Features a portrait of the legendary Japanese hero-statesman Takenouchi no Sukune.
Reverse: Depicts the Ube Shrine.
Color and Size: The obverse is predominantly black on a light blue or brown underprint, while the reverse is orange. It measures 81 mm x 142 mm.
Security Features: Includes paulownia watermarks when held up to a light source.
Historical Context:
Issuance: Released on December 15, 1943, during Japan's involvement in World War II.
Purpose: Unlike earlier yen banknotes, the 1943 issue was not convertible to silver and was introduced as fiat currency due to wartime economic realities and the reorganization of the Bank of Japan.
Production Quality: These notes were produced under wartime budget cuts, leading to a shift from mitsumata paper to pulp and simplified printing and design.
Collector's Value:
Legal Tender: While technically still legal tender in Japan, their collector's value significantly exceeds their face value making them valuable.