TOKYO (Kyodo) -- A silver seal used by the Tokugawa shogunate to sign diplomatic documents in the 19th century has been found and will go on display from next month.
The memorial foundation of the family and some experts said Monday that the seal, known as "keibun ibu," was used by the 14th Shogun Iemochi and 15th and last Tokugawa Shogun Yoshinobu to ratify diplomatic documents as head of state.
The signings on treaties with Western nations such as the 1858 Treaty of Amity and Commerce with the United States, which reopened Japan after more than 200 years of seclusion, triggered criticism domestically that the shogunate failed to revere the emperor, and accelerated movement to overthrow the feudal government.
Made by seal engraving artist Koen Masuda, the seal weighs 2.7 kilograms and is 9.2 centimeters in length and width and 7.8 cm in height. It was found last year in a Tokugawa family storehouse, according to the Tokugawa Memorial Foundation.
It will go on display from Sept. 15 in an exhibition at the Niigata Prefectural Museum of History in the central Japan city of Nagaoka.