Ii Naosuke

Ii Naosuke (1815-1860) was the daimyō of the Hikone Domain in Ōmi (present-day Hikone City, Shiga Prefecture) and a statesman who, as Tairō (Great Elder) of the Edo shogunate, shaped the political situation of the late Edo period. He became Tairō in Ansei 5 (1858), signed the Japan–US Treaty of Amity and Commerce, and carried out the opening of the country. He suppressed his opponents in the Ansei Purge, but on 24 March 1860 (Ansei 7/3/3) he was assassinated outside Sakuradamon of Edo Castle by rōnin from the Mito and Satsuma domains who had left their domains. This "Sakuradamon Incident" became the trigger for the collapse of the shogunate's authority.

Naosuke was born in Bunka 12 (1815) as the fourteenth son of Ii Naonaka, lord of the Hikone Domain. Having many elder brothers, he was for a long time not a successor candidate, and he spent about fifteen years in a modest residence called "Umoregi-no-ya." During this "Umoregi-no-ya period" he studied the tea ceremony (Sekishū-ryū), Noh, swordsmanship, and many other arts and martial arts, and cultivated depth of thought. In Kaei 3 (1850) he became lord of the domain, and in Ansei 5 (1858) he became Tairō under Tokugawa Iesada.

After taking office as Tairō, Naosuke negotiated with the American consul general Townsend Harris and signed the Japan–US Treaty of Amity and Commerce without obtaining imperial sanction. This high-handed action drew fierce criticism from the Imperial Court and the expel-the-barbarians faction. Furthermore, in the shogunal succession question, he suppressed the faction of Hitotsubashi Yoshinobu and decided that Tokugawa Yoshitomi of Kii (later Iemochi) would be the shogun's successor. He carried out the suppression of his opponents as the Ansei Purge, and he had Yoshida Shōin, Hashimoto Sanai, and others executed. However, on 24 March 1860 (Ansei 7/3/3), on his way to the castle from the Hikone domain residence, he was assassinated outside Sakuradamon by eighteen rōnin from the Mito and Satsuma domains.

In relation to the Japanese sword, Naosuke had deep knowledge of swordsmanship and sword culture. During the Umoregi-no-ya period he studied iai, and later he founded the iai school "Shinshin Shin-ryū" himself. Naosuke was a lord who valued the martial arts. In the Sakuradamon Incident, the scene in which many Mito rōnin fought a desperate battle with Japanese swords against the Hikone retainers guarding him is passed down as the final fierce struggle between Japanese swords and samurai in the late Edo period. It is said that Naosuke was first shot with a pistol and could not move from his palanquin, and that many of the Hikone retainers guarding him were cut down without being able to draw their swords, blocked by the hilt covers (tsuka-bukuro) they had put on against the snow.