Ansei Purge

The Ansei Purge was a 1858–1859 campaign by the Tokugawa shogunate to punish political opponents of its succession choices and foreign-treaty policies.

Ii Naosuke: Ii Naosuke was a Tokugawa elder who became chief minister and directed the Ansei Purge. As chief minister, he ordered the arrests and punishments that defined the campaign.
Tokugawa succession dispute: The 1858 dispute over who would succeed Tokugawa Iesada as shogun, principally Iemochi or Yoshinobu. The purge followed the victory of Iemochi’s supporters over the Yoshinobu faction.
Sakuradamon Incident: The 1860 assassination of Ii Naosuke outside Edo Castle by rōnin opposed to his policies. The killing was a direct reprisal against the purge’s chief architect.
Yoshida Shōin: Yoshida Shōin was a Japanese political thinker and educator executed by the shogunate in 1859. His execution made him one of the purge’s best-known victims and a symbol of resistance.
Tokugawa Iemochi: Tokugawa Iemochi was the fourteenth shogun of Japan, chosen as successor amid a contested succession. His selection over Tokugawa Yoshinobu helped ignite the political conflict behind the purge.
Tokugawa Iesada: Tokugawa Iesada was the thirteenth shogun of Japan, whose failing health left the succession unresolved. His impending death made the choice of successor urgent and politically explosive.
Bakumatsu: Bakumatsu is the final period of Tokugawa rule in Japan, from the opening of the country in the 1850s to 1868. The purge belongs to the growing crisis that brought the shogunate to its end.
Hashimoto Sanai: Hashimoto Sanai was a Fukui-domain adviser executed in 1859 for his political involvement and support of Yoshinobu’s succession. His death shows that the purge reached influential domain officials, not only public agitators.
Tokugawa Yoshinobu: Tokugawa Yoshinobu was a Tokugawa prince whose candidacy for shogun attracted powerful supporters in 1858. Supporters of his succession were among the purge’s principal targets.
Harris Treaty: The 1858 treaty between the United States and Japan that opened ports and established unequal commercial terms. Its signature without imperial consent sharpened the dispute over the shogunate’s authority.

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