Many of the lines from this movie are sampled by hip-hop artist and Wu-Tang Clan member the GZA on his album "Liquid Swords".
This movie is watched by The Bride and her daughter at the end of Kill Bill vol ll
Mark Lindsay (former lead singer for Paul Revere and the Raiders) co-wrote the music with W. Michael Lewis. The performing credit is listed as "The Wonderland Philharmonic." "Wonderland" refers to the house that Lindsay lived in at one time. However, music cues from the original "Kozure Ôkami" films are also used.
The symbol that appears through the credits is the official family crest (or Mon) of the powerful Tokugawa clan, which ruled Japan as Shoguns from 1603 until the end of the Edo (Tokugawa) period in 1868. These symbols were similar in function to flags, and like flags, it was considered sacrilegious to desecrate or destroy them.
This film is made up from the first two installments of the "Lone Wolf and Cub series". This is also mentioned in the DVD commentary of Shogun Assassin.