While it is considered that many of jinko were Bemin (people who belonged to Yamato Court) which date back to the period before the Taika Reforms, jinpu is considered to have originated as part of Jikifu system (a kind of stipend; fuko are given as an income source) under the Ritsuryo system (a system of centralized government based on the ritsuryo code).
神戸の多くが大化前代に遡ることが出来ると考えられる所謂部民であったと考えられるのに対して、神封は律令制による食封制度の一環として成立したと考えられている。