The term Rikkokushi (literally "six national histories") denotes a corpus of six official chronicles produced by the Japanese court in the 8th and 9th centuries. Written in classical Chinese, these works combine myth, genealogy, court annals and reports of major events to present a continuous narrative of ruling houses, ceremonies and political developments up to the late ninth century.

Works that make up the Rikkokushi

  • Nihon Shoki (日本書紀)
  • Shoku Nihongi (続日本紀)
  • Nihon Kōki (日本後紀)
  • Shoku Nihon Kōki (続日本後紀)
  • Nihon Montoku Tennō Jitsuroku (日本文徳天皇実録)
  • Nihon Sandai Jitsuroku (日本三代実録)

These texts were compiled under imperial authority and modeled on Chinese historiographical practices. The best known of them, Nihon Shoki, was completed in the early 8th century and sets a literary and institutional precedent for the later volumes. Together they record events, edicts, genealogies, natural phenomena and ceremonial rites regarded as important by the court.

The Rikkokushi are primarily written in kanbun (classical Chinese used in East Asia), reflecting both the cultural influence of Tang China and the formal style expected of state histories. Entries vary from short annalistic notices to longer biographical or diplomatic reports; they sometimes incorporate earlier documents, official memoranda and poetic passages.

Importance and uses: scholars rely on the Rikkokushi as fundamental primary sources for the Nara and early Heian periods. They are essential for reconstructing imperial succession, court ranks and legal reforms, and for tracing how myth and ritual were employed to legitimize political authority. Because they were official records, they also reveal the priorities and self-image of the central government.

Notable issues and distinctions: the Rikkokushi differ from the Kojiki, an earlier vernacular chronicle with a stronger focus on myths and oral tradition. While comprehensive, some volumes of the national histories have been partially lost or survive only in later copies and excerpts; historians therefore compare them with temple records, private diaries and archaeological evidence to build a fuller picture of early Japan.