Jinpu is fuko (a vassal household allotted to courtier, shrine and temple) donated to a shrine.
The residents of jinpu served the shrine by paying tax, performing allocated jobs, serving as Hafuri (an ancient Shinto priest) or other posts, and so on. These residents are called "Jinfuko."
Although it is generally deemed to be synonymous with "jinko" (also known as "kanbe," written as 神戸 or 神部 in Chinese characters), it is considered that their period of origin and original role were different with each other; it is considered that the two became increasingly confused from the late Nara period to the early Heian period.
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). However, there are no definite rules about it in the Yoro Code and so on; it is only mentioned in Zhu Theory (notes which is said to be written by Judicial Officials) in the external ordinance of Rokuryo in "Ryonoshuge" (Commentaries on the Civil Statutes). Therefore, provisions for jinpu was made in Daijokanpu (official documents from Daijokan [Grand Council of State] to local governments) and Daijokancho (official documents from Daijokan to Buddhist temples).
Originally, unlike jinko, only Yo (tax in kind), Cho (tributes), and allocated job were imposed on jinfuko, under the provision for fuko in Fuyaku ryo (tax law); they paid half of denso (rice field tax) to the shrine, and another half to the state. However, the difference from jinko in the tax system disappeared when it was decided in 739 that fuko should pay all the rice tax to fushu (in case of jinpu, fushu is the shrine). About that time, a new system was introduced: Shrines were conferred Ikai (Court rank) and Ifu (fuko which were given according to ikai) like government officials (especially one of low to medium rank); the number of ifu for a shrine was the same as that for a government official of the same ikai (however, according to the records in "Shoku Nihongi" [Continuation of Chronicles of Japan] and so on, there were cases in which ifu were not paid in full). It was also treated as jinpu.
In the early Heian period, jinko and jinpu, making no actual difference with each other, began to be confused and treated as the same. In Daijokancho written in 806 and carried on "Shinsho kyakuchoku fusho," they were treated as the same kind; it is presumed that they were considered to be the same in those days.