Japanese Stamps Digital Museum

第1次昭和切手 << 1937年(昭和12年) ~ 1940年(昭和15年) >>  みほん 1-8-1

First Showa Stamps Issued on 1937 (Showa 12) - 1940 (Showa 15) - Specimen -

First Showa Stamps Issued on 1937 (Showa 12)-1944 (Showa 19) - Specimen - In 1937, the Sino-Japanese war began. From this time on, Japanese stamps became more war-colored, and until the year 1946 (Showa 21), the year after the end of the war, stamps with a design based on the idea of a military nation were issued. Showa stamps are classified into the 1st Showa (when the Sino-Japanese War started), the 2nd Showa (when the Pacific War broke out), and the 3rd Showa stamps (when supplies were insufficient). Since it was published during the turbulent times, there are numerous changes and errors.

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The above is only true for specimen stamps.
For more information and official printed stamps, see this.
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