The Kinmon incident (禁門の変, Kinmon no Hen, "Forbidden Gate Incident" or "Imperial Palace Gate Incident"), also known as the Hamaguri Gate Rebellion (蛤御門の変, Hamaguri Gomon no Hen, "Hamaguri Imperial Gate Incident"), was a rebellion against the Tokugawa shogunate in Japan that took place on August 20 [lunar calendar: 19th day, 7th month], 1864, near the Imperial Palace in Kyoto.