The tradition says that this tantō was once owned by an envoy of an unknown name who was sent to Ming-China at the beginning of the Muromachi period. His mission was connected with the erection of Kyōto´s Tenryūji (天龍寺).*1 On the way to his destination he and his men were suddenly surrounded by five tigers. In panic he drew his dagger and started to wave it around like a maniac. But it helped and the big-cats went away.
Back home in Kyōto he proudly told this story to the then shōgun Ashikaga Yoshimitsu (足利義満, 1358-1408) by saying: “With this dagger I alone drove away (Jap. shirizokeru/tai, 退) five tigers (Jap. goko, 五虎)!” Thereupon the tantō by Awataguchi Yoshimitsu (粟田口 吉光) received the nickname Gokotai-Yoshimitsu (五虎退吉光).
Somewhat later it is said that it came into the possession of Nōami (能阿弥, 1397-1471) who was the artistic advisor of the Ashikaga family. At the end of the Muromachi period it was owned by emperor Ōgimachi (正親町天皇, 1517-1593), and when Uesugi Kenshin visited Kyōto in Eiroku two (永禄, 1559) to attend an important audience with shōgun Ashikaga Yoshiteru (足利義輝, 1536-1565) and Ōgimachi, he was presented with the dagger Gokotai-Yoshimitsu. Thereupon it became a heirloom of the Uesugi family.
About 400 years later, or to be more precise in October 1881, emperor Meiji visited the northern Yonezawa which was ruled by the Uesugi during the feudal years. Everybody knew that the emperor was a sword lover and so he was shown several pieces of the former Uesugi collection. Even late at night he still asked for more blades and so it was decided to extend the stay for another day and night. Miyajima Seiichirō (宮島誠一郎, 1838-1911), the then secretary of the Imperial Household Agency who attended Meiji, noted the entire trip in detail.
At one poiny the Gokotai-Yoshimitsu was brought and handed over to the emperor. He was carrying a dagger by Awataguchi Yoshimitsu that he received from his predecessor emperor Kōmei (孝明天皇, 1846-1866) and compared it with the piece from the Uesugi collection: “The length is the same, also the deki, what is the opinion of the Hon´ami expert?” When the latter joined the group and had examined the two blades carefully he turned to Meiji and said: “I think that the sword of Your Highness has to be rated somewhat higher.” And the emperor laughed and replied: “Well, then I should be able to ward off ten tigers with it!”
tantō, mei “Yoshimitsu” (吉光), nagasa 24.8 cm, takenokozori
*1 The construction of the temple was initiated in 1339 by Ashikaga Takauji and it was completed in 1345. In the year 1342 trading ships were sent to China to find more money to fund the continuation of the temple’s construction.