Kojiki(古事記?, "Records of Ancient Matters" or "An Account of Ancient Matters") is the oldest extant chronicle in Japan, dating from the early 8th century (711–712) and composed by Ō no Yasumaro at the request of Empress Gemmei. The Kojiki is a collection of myths concerning the origin of the four home islands of Japan, and the Kami. Along with the Nihon Shoki, the myths contained in the Kojiki are part of the inspiration behind many practices. Later, the myths were re-appropriated for Shinto practices including the misogi purification ritual.
The Kojiki contains various songs/poems. While the historical records and myths are written in a form of Chinese with a heavy mixture of Japanese elements, the songs are written with Chinese characters that are only used to convey sounds. This special use of Chinese characters is called Man'yōgana, a knowledge of which is critical to understanding these songs, which are written in Old Japanese.
The Nakatsumaki begins with the story of Emperor Jimmu, the first Emperor, and his conquest of Japan, and ends with the 15th Emperor, Emperor Ōjin. The second through ninth emperors' reigns are recorded in a minimum of detail, with only their names, the names of their various descendants, and the place-names of their palaces and tombs listed, and no mention of their achievements. Many of the stories in this volume are mythological, and the allegedly historical information in them is highly suspect. Recent studies support the view that these emperors were invented to push Jimmu's reign further back to the year 660 BC.
The Shimotsumaki covers the 16th to 33rd emperors and, unlike previous volumes, has very limited references to the interactions with deities. These interactions are very prominent in the first and second volumes. Information about the 24th to the 33rd emperors are largely missing, as well.
There are two major branches of Kojiki manuscripts: Ise and Urabe. The extant Urabe branch consists of 36 existing manuscripts all based on the 1522 copies by Urabe Kanenaga. The Ise branch may be subdivided into the Shinpukuji-bon (真福寺本?) manuscript of 1371–1372 and the Dōka-bon (道果本?) manuscripts. The Dōka sub-branch consists of:
the Dōka-bon (道果本?) manuscript of 1381; only the first half of the first volume remains
the Dōshō-bon (道祥本?) manuscript of 1424; only the first volume remains, and there are many defects
the Shun'yu-bon (春瑜本?) manuscript of 1426; one volume
The Shinpukuji-bon manuscript (1371–1372) is the oldest existing manuscript. While divided into the Ise branch, it is actually a mixture of the two branches. The monk Ken'yu based his copy on Ōnakatomi Sadayo's copy. In 1266, Sadayo copied volumes one and three, but did not have access to the second volume. Finally, in 1282, he obtained access to the second volume through a Urabe-branch manuscript that he used to transcribe.