The Class-E10 was a type of 2-10-4 steam locomotive built by the Japanese Government Railways (JGR) beginning in 1948, and were the largest tank engine built in Japan.
Following the end of World War II Japanese Government Railways was prohibited by GHQ, the Allied Occupation headquarters, from building new locomotives due to financial difficulties. However, an exception was granted for building the E10s to replace the ageing JNR Class-4110 locomotives. This was because it was not possible to substitute existing locomotives on the steep gradients of the Ōu Main Line (from Fukushima Station through Akita Station to Aomori Station, completed in 1905) where the 4110s were used.
Five E10 locomotives were manufactured at the Kisha Seizo Kaisha factory, in Osaka, in 1948 .These were the last steam locomotives built for Japanese National Railways.
The last examples in regular service were withdrawn in 1962. One E10 remains in preservation: E10-2 (seen in the postcard image, above) is displayed at Ome Railway Park, at Ōme, Tokyo.