The Shinsengumi was a small, elite group of swordsmen that was organized by commoners and low rank samurai, commissioned by the bakufu during Japan's Bakumatsu period in 1863. It was active until 1869. It was founded to protect the shogunate representatives in Kyoto at a time when a controversial imperial edict to exclude foreign trade from Japan had been made and the Chōshū clan had been forced from the imperial court. They gained considerable fame in the Ikedaya incident and the August 18 coup events, among others. The men were drawn from the sword schools of Edo.

Bakumatsu was the final years of the Edo period when the Tokugawa shogunate ended. Between 1853 and 1867, under foreign diplomatic and military pressure, Japan ended its isolationist foreign policy known as sakoku and changed from a feudal Tokugawa shogunate to the modern empire of the Meiji government. The major ideological-political divide during this period was between the pro-imperial nationalists called ishin shishi and the shogunate forces, which included the elite shinsengumi swordsmen.