Ruiju Kokushi (Volumes 165, 171/177, 179)

What Is Ruijū Kokushi?

The Ruijū Kokushi (literally "Classified National History") is a monumental reference work compiled in 892 by Sugawara no Michizane (845–903), the celebrated scholar-statesman later deified as the god of learning, Tenjin. Working under a direct imperial command from Emperor Uda, Michizane reorganised the entire body of Japan's "Six National Histories" — the Rikkokushi — into a thematic encyclopaedia.

Those six chronicles, beginning with the Nihon Shoki (720) and ending with the Nihon Sandai Jitsuroku (901), formed the official record of the Yamato court. They were, however, organised strictly by date. Michizane saw that for court officials who needed to cite precedent — the correct ritual for a solar eclipse, the established response to an earthquake, the proper form for an ordination — chronological ordering was nearly useless. He therefore extracted every passage and re-arranged it by subject, preserving the original wording without alteration.

The completed work ran to 200 volumes of main text, 2 volumes of catalogue, and 3 volumes of imperial genealogy — 205 scrolls in total. It was, in effect, the first large-scale thematic encyclopaedia of Japanese history. After the Ōnin War of the late fifteenth century, however, most of it was lost. Only 61 volumes plus scattered fragments survive today, which is what makes every surviving ancient manuscript, and particularly the four held at the Sonkeikaku Bunko, so precious.

The Four Volumes and Their Contents

The four scrolls are not a continuous run but a scattered sampling from across Michizane's classification scheme. Each one opens onto a completely different corner of Heian life.

Volume 165 — Auspicious Omens, Part 1. This scroll belongs to the Shōzui section, which gathers reports of heavenly and natural signs believed to reveal the will of the gods. The entries catalogue remarkable appearances of the sun, moon, and stars; unusual clouds, rainfall, dew, and snow; and an astonishing bestiary of birds — pheasants, wild geese, hawks, cormorants, crows, swallows, sparrows, doves, kites, owls, and wrens — whose untimely flocking or unusual colours were read as messages from the cosmos to the throne.

Volume 171 — Calamities, Part 5: Earthquakes. This is perhaps the most historically consequential of the four. It gathers every earthquake record extracted from the Six National Histories, and it is the primary surviving source for the Kōnin Earthquake of 818, which devastated the Kantō region. The account describes mountains collapsing, valleys filled for leagues, and uncountable dead — one of the earliest detailed earthquake descriptions in East Asian historiography, and a text modern seismologists still consult.

Volume 177 — Buddhism, Part 4. This volume is devoted to the great Buddhist ceremonies of the imperial court: the Ninnō-e for the protection of the state, the Gosai-e of the New Year, the Yuima-e at Kōfuku-ji, the Saishō-e, the Monju-e for Mañjuśrī, and the spectacular Mantō-e "ten thousand-lamp" rites. It is a key document for understanding how Buddhism had, by the ninth century, woven itself into the annual rhythm of the state.

Volume 179 — Buddhism, Part 6. Here the subject shifts to the Buddhist schools themselves: the approved sects, the granting of ordinations, and the career pathways of monks. It offers a rare statistical glimpse of the early Heian Buddhist establishment at work.

Why This Manuscript Was Designated a National Treasure

The Japanese government designated these four volumes a National Treasure on 14 November 1953, and the reasoning rests on three intertwined grounds. First, they are among the very oldest surviving copies of Ruijū Kokushi — produced in the late Heian period, close in time to the lost original. Every word they preserve is irreplaceable evidence of Michizane's text.

Second, they are a primary tool for reconstructing the Nihon Kōki, one of the Six National Histories of which only a small portion has come down to us. Because Michizane's compilation method was strictly faithful to the source — genbunshugi, or "original-text principle" — passages he quoted from now-lost chronicles are treated by scholars as direct evidence of what those chronicles once contained.

Third, the four volumes carry a distinguished provenance that guarantees their authenticity. They descended through the Mibu Kanmu family, a hereditary line of senior bureaucrats in the Grand Council of State who kept the court's working archive; in 1705 they were acquired by Maeda Tsunanori, the fifth lord of Kaga and one of the most bibliophilic daimyō in Japanese history, who absorbed them into the Sonkeikaku collection where they have remained ever since.

Highlights: What Makes These Scrolls Remarkable

The hand of a vanished world. The brushwork is that of a late-Heian scribe — measured, columnar, strikingly different from later calligraphic fashions. To read it is to stand shoulder to shoulder with a copyist working perhaps seven or eight hundred years ago on paper that has somehow outlasted wars, fires, and the Ōnin catastrophe.

A direct voice from the court. Because Michizane refused to paraphrase, the scrolls preserve the exact phrases used by imperial chroniclers of the eighth and ninth centuries. Reading Volume 165's entries on auspicious birds, or Volume 171's earthquake accounts, one encounters Heian Japan in its own words.

A scientific record of disaster. Volume 171 is still being mined by earthquake scientists. The 818 Kōnin Earthquake entry — describing landslides along the southern flanks of Mount Akagi — has been correlated with geological evidence at the actual site, a rare case where a Heian text and the modern fieldwork of seismologists confirm one another.

A precedent manual for the Heian state. These volumes were not ornaments. They were working reference tools consulted by officials needing to know how their predecessors had handled ordinations, ceremonies, and emergencies. Holding them, one holds the equivalent of a ninth-century government handbook.

Visiting and Viewing Information

Visitors should be aware of an important fact before planning a trip: the Sonkeikaku Bunko, which holds these four volumes in Meguro, Tokyo, is a research-only institution. Access is limited to credentialed scholars with prior permission, and the scrolls themselves are not placed on regular public display.

However, the Maeda Ikutokukai periodically lends materials for special exhibitions at the Ishikawa Prefectural Museum of Art in Kanazawa, where a dedicated Sonkeikaku Bunko Annex gallery presents rotating selections from the collection. These Ruijū Kokushi volumes have been displayed there on rare occasions, most recently as part of exhibitions surveying the arts of the Kaga domain.

Travellers interested in the Maeda legacy can, in the meantime, freely visit the grounds of Komaba Park in Tokyo, which sits beside the Sonkeikaku Bunko. Here one can tour the Former Maeda Family Residence — both the Western-style mansion and the Japanese-style house — which is itself an Important Cultural Property and evokes the splendour of the family that preserved these manuscripts.

Surrounding Attractions

The Komaba neighbourhood rewards unhurried exploration. Within a short walk of the Sonkeikaku Bunko stand several notable destinations that together make for a rich cultural afternoon.

• Former Maeda Family Residence (Komaba Park) — a 1929 Western-style mansion designed by Takahashi Teitarō, with an adjoining Japanese-style residence, both designated Important Cultural Properties
• Japan Folk Crafts Museum (Nihon Mingeikan) — founded by Yanagi Sōetsu, a celebration of anonymous craft traditions, a five-minute walk away
• Komaba Campus of the University of Tokyo — the former site of the imperial agricultural college, with tree-lined avenues and historical architecture
• Ishikawa Prefectural Museum of Art (Kanazawa) — for those willing to travel, the only place where objects from the Maeda collection are regularly displayed, located next to Kenroku-en Garden
• Seisonkaku (Kanazawa) — a historic residence built by the thirteenth Kaga lord, displaying Maeda family furnishings and armour