"Shogun Assassin" was edited and compiled from the first two films in the "Lone Wolf and Cub" series, using 12 minutes of the first film, ' ("Kozure Ōkami: Kowokashi udekashi tsukamatsuru" or "Wolf with Child in Tow: Child and Expertise for Rent"), and most of ' ("Kozure Ōkami: Sanzu no kawa no ubaguruma" or "Wolf with Child in Tow: Perambulator of the River of Sanzu"). Both were originally released in 1972. There were six films in all in the series. These, in turn, were based on the long-running 1970s manga series "Lone Wolf and Cub" created by the writer Kazuo Koike and the artist Goseki Kojima.