Kanbunden is a style of biography written in classical Chinese, influenced by Kidentai (an East Asian historical writing style) of Chinese authentic history and Kokushitai (Japanese historical writing style) of Japanese authentic history.
A Japanese authentic history, Rikkokushi (6 histories of the nation), basically maintains the appearance of Hennentai (a chronological writing style) in classical Chinese, but in the 5 histories other than "Nihonshoki," the biographies of high officials or high-rank priests were added in the descriptions of their deaths (Kokushitai). In early times those descriptions were only about their achievements, but later various episodes were also added. By the influence of those histories of Japan and series of biographies of major Chinese history books such as "Shiki," biographies used to be written for rewarding individuals.
In the Nara period, the biography of the FUJIWARA three generations began with FUJIWARA no Kamatari, "Kaden" (Family history) and "Shotokutaishi Denryaku" (Biography of Shotokutaishi) were written, and in the Heian period MIYAKO no Yoshika (the compiler of an authentic history "Nihon Montoku Tenno Jitsuroku" [Fifth of the six official national history books]) wrote "Dojo Hoshi Den" (Biography of Dojohoshi), Kiyoyuki MIYOSHI wrote "FUJIWARA no Yasunori den" (Biography of FUJIWARA no Yasunori) and "Enchin Osho Den" (Biography of Enchin), and KI no Haseo wrote "Tsunesada Shinno Den" (Biography of Imperial Prince Tsunesada). Also, more creativity-conscious books than historical facts, such as "Zoku Urashima Den" (Sequel of the folklore, Taro Urashima [Rip van Winkle]) of unknown authorship, appeared, which influenced the subsequent narrative literature.