Sendai Kujihongi (先代旧事本紀)

Sendai Kujihongi is a book on ancient Japanese history. Scholastically speaking, it is considered a forged document. Some view that the document has partial documentary value (to be explained later). The document is also called "Kujiki" or "Kujihongi." It consists of 10 volumes with historical documentation from the birth of the world (Japanese myth) to the time of Emperor Suiko. Sendai Kujihongi Taiseikyo' (Enpo Edition) and two others, are forged documents (Koshi Koden (Ancient History and Legends)) written during the Edo period, based on the Sendai Kujihongi.

Establishment/Author
In the prologue, it is stated that the document was written by Prince Shotoku and SOGA no Umako upon the order of Emperor Suiko (similar statement can be found in "Nihonshoki" (Chronicles of Japan) in the twenty-eighth year of the reign of Emperor Suiko (620)). From this time on, during the time from the Mid-Heian period up to the Mid-Edo period, the document was respected as the oldest historical text, more so than the "Kojiki" (The Records of Ancient Matters) or the "Nihonshoki" (Chronicles of Japan). During the Edo period, the document was questioned as being forged, and the study conducted by Mitsukuni TOKUGAWA and Sadatake ISE revealed that the document was in fact a forgery. The document was assumed to be written after the Daido period (806-810) and before the Engi Shoki Koen (lecture on the "Chronicles of Japan" in the Engi Era) (904-906).

Most parts of the document are patchworks of texts from the "Kojiki," "Nihonshoki" and "Kogo-shui" (History of the Inbe clan); however, there are some areas describing traditions and deities that are unique to the document. There are particularly extensive descriptions related to Nigihayahi (child of Tenjin (god of heaven)), the Soshin (ancestor honored as god) of the Mononobe clan, which led to opinions that the text were extracted from a Mononobe document, a document that no longer exists. A Japanese classical literature scholar, Kiyonao MIKANNAGI (1812-1892) named OKIHARA no Miniku, a teacher of law in the Ritsuryo System, as the possible compiler of the document. OKIHARA no Miniku belonged to the Mononobe clan (his original name was MONONOBE no Okihisa), and he was most active during the period when the "Sendai Kujihongi" was written. There are other theories as to who the compiler was other than OKIHARA no Minoku, and some of the candidates that came up were Shinto priests of the Isonokami-jingu Shrine, Yakatsugu ISONOKAMI and YATABE no Kinmochi.

Public estimation
In the prologue of the document, it states that it was written by Prince Shotoku and SOGA no Umako, and was respected by Shintoists during the Middle Ages.

Jihen, a priest during the Kamakura period, wrote a commentary, "Kuji Hongi Gengi" (Deep Significances in the Kuji hongi) with the thought that the "Sendai Kujihongi" was the core of the Shinto concept, influencing Watarai Shinto (A school of Shinto teachings expanded by priests of the Watarai clan at the Outer Shrine (Geku) of the Ise-jingu Shrine).

Yoshida Shinto, which was established by Kanetomo YOSHIDA during the Muramachi period, also valued the "Sendai Kujihongi" and considered the "Kiki" (the Kojiki and Nihonshoki), the "Sendai Kujihongi" and this document as the 'Sanbu no Honsho' (three books of origin).

With the descriptions regarding the establishment of the document in the prologue being under question, and Mitsukuni MITO, Yoshitoshi TADA, Sadatake ISE and Norinaga MOTOORI defining it as a forged document, it is now generally viewed as forgery. During the Meiji period and thereafter, some scholars theorized that, putting aside the description in the prologue about how the document came about, the main contents are not forged; however, in recent studies, with the consistency of the contents of the document itself, as well as the consistency of the contents with other documents, the public is leaning to the opinion that the entire document was forged.

However, there are some accounts unique to the document not existing in other documents, including the sections on Tenjin Hongi (the original record of the heavenly deity) in volume 3; Tenson Hongi (the original record of the heavenly grandchild) in volume 5 that tells about the Owari clan and a story about the Mononobe clan (related to Nigihayahi no mikoto); and the Kokuzo Hongi (the original record of provincial governors) in volume 10. Some comment that there are excerpts from a Mononobe document, a document that no longer exists, in the section on Tenjin Hongi, and is valuable as a historical document for its description on the creation of Japan, along with the Kokuzo Hongi (the original record of provincial governors).

Structure
Jinno Keizu (Genealogy of divine sovereigns) Volume 1 -Currently missing

Volume 1 Jindai Hongi (the original record of the age of the kami), Jindai Keiki (genealogy of divine age), Inyo hongi (the original record of yin and yang), the Izanagi Myth, a creation of heaven and earth (Japanese myth)

Volume 2 Jingi Hongi (the original record of divine worship), Pledge of Amaterasu (the Sun Goddess) and Susanoo, the Exile of Susanoo

Volume 3 Tenjin Hongi (the original record of the heavenly deity), Nigihayahi (child of Tenjin (god of heaven)) Myth, Izumo Kuniyuzuri (transfer of the Izumo land)

Volume 4 Chigi Hongi (the original record of earthly deity worship) (Ichiden, Chishin Hongi), Izumo Myth

Volume 5 Tenson Hongi (the original record of the heavenly grandchild) (Ichiden, Koson Hongi), the Genealogy of the Mononobe clan and Owari clan

Volume 6 Koson Hongi (the original record of the imperial grandchild) (Ichiden, Tenson Hongi), Himuka Sandai (three generations of Himuka), Jinmu Tosei (story in Japanese myth about the first generation of the Imperial Family)

Volume 7 Tenno Hongi (the original record of heavenly sovereigns), from Emperor Jinmu to Empress Jingu

Volume 8 Shinno Hongi (the original record of divine sovereigns) from Emperor Ojin to Emperor Buretsu

Volume 9 Teio Hongi (the original record of Imperial Family) from Emperor Keitai to Emperor Suiko

Volume 10 Kokuzo Hongi (the original record of provincial governors), stories of 135 provincial governors