Tantou(短刀)Yoshimitsu(吉光) 7寸2分 Mid-Kamakura (13th century)
The Japanese people start calling their sword as “Japanese sword” around the end of Tokugawa Shogun period(19th century) when they reopened the gates for the foreign countries for the foreign trades. Before that period, the Japanese swords were just called as “Katana(刀)” or “Tsurugi(剣).” After Muromachi (室町)period (around A.D.1,500), the Japanese swords were classified into three different categories based on their length.
Uchikatana(打刀) over 60cm
Wakizashi(脇差) 30cm〜60cm
Tantou(短刀) less than 30〜36cm
In Muromachi period, they used their swords on horses in the battles so that swords were long with large curve shapes. They were called Tachi(太刀)and their length are about 75.8〜78.8cm long. When they carried Tachi putting on a sword with its edge down. On the other hand, Uchikatana was put on between belts with its edge up.