Niimi Nishiki or Shinmi Nishiki (jap. 新見 錦; b. 1836 in Mito; October 19, 1863 in Kyōto) was one of three commanders, later vice-commander, of the Shinsengumi, a Japanese police unit of the Bakumatsu period (1853-1867) that patrolled Kyōto.
The continuous opening of Japan in the 1960s, which began with Matthew Perry's arrival, caused much controversy among the population. Therefore, various military movements arose, causing great unrest in the country.
Some fought for the opening of Japan and the associated retention of power by the Tokugawa Shōgunate. Others made their presence felt, for example, with the Sonnō-jōi slogan, demanding that power be returned to the Tennō, the Japanese emperor, and thus voting against Western foreign countries.
The Rōshigumi was a fighting force recruited by the Shōgun to maintain peace and order in Kyoto. However, many of the fighters were more inclined toward the emperor, and so most were sent to Edo (modern Tokyo), where they caused little trouble. Among those who remained in Kyoto were the later members of the Shinsengumi.
Niimi was born in Han Mito (present-day Ibaraki Prefecture). He became a member of the Rōshigumi, where he belonged to the faction of commander Serizawa Kamo after a division became apparent within the group between Serizawa and the second commander, Kondō Isami.
When the leader of the Rōshigumi, Kiyokawa Hachirō wanted the force to fight for the Emperor's Loyalists, Niimi remained in Kyōto and was then one of the 13 founding members of the Shinsengumi.
He was originally a commander as well, along with Serizawa and Kondō, but was later downgraded to the position of vice-commander.
Because he was an important member of the Serizawa faction that the Kondō followers wanted to disband, he was probably forced to commit seppuku (ritual suicide) by Hijikata Toshizō and Yamanami Keisuke on October 19, 1863 (September 10 according to the lunar calendar).
There is also a theory that he was killed by a samurai from Mito, as he is said to have killed a member of the Shinsengumi, but this is rather unlikely.
Even though he had taken the name Niimi Nishiki, his real name remains unknown. He must have been educated, however, since his name plays with pronunciation.
There is speculation that he may have been a spy from Chōshū, and that he had close ties to Sonnō-jōi groups in Mito and Tosa who, unlike the Shinsengumi, supported the emperor.