Short Sword (Meirai Kunitoshi)

What This Tantō Is

A tantō is a Japanese short sword or dagger, traditionally worn alongside a longer blade. This particular example was forged by Rai Kunitoshi, a master swordsmith of the Rai school (来派), one of the most celebrated lineages of swordmakers based in Kyoto during the late Kamakura period. The blade carries his three-character signature "来国俊" carved into the tang, leaving no doubt as to its maker.

The sword measures 24.5 centimeters in cutting edge length, with a base width of 2.1 centimeters and a tang nearly 9.3 centimeters long. It weighs approximately 150 grams. The form is graceful: a gently curved "furisode" shape (named for the long swinging sleeves of formal kimono), with a flat construction known as hira-zukuri and a three-faceted ridge along the back called mitsu-mune. On one face, the smith carved twin parallel grooves representing ritual goma sticks; on the reverse, a shorter waist-groove called koshi-bi adorns the blade.

Historical Background

The Rai school flourished in Yamashiro province, the cultural heart of medieval Japan surrounding the imperial capital of Kyoto. According to a fifteenth-century swordsmith genealogy known as the "Mei-zukushi," the school's ancestors are said to have come from the Korean peninsula, though the lineage's true founding figure in surviving historical record is Kuniyuki, who worked in the mid-Kamakura period.

Rai Kunitoshi was active from at least 1278 through 1321 — an unusually long career. A blade he signed in 1316 records his age as seventy-five, allowing scholars to estimate his birth around 1241. His earlier works tend to be powerful and dramatic, decorated with the flame-like clove-blossom temper pattern called chōji-midare. In his later years he refined his style toward elegant slender forms with the calm, straight temper line known as suguha. Most surviving Rai Kunitoshi works belong to this later period, and contemporary connoisseurs considered him especially gifted at producing tantō.

The Kurokawa tantō ranks among his masterpieces. The official designation record describes the blade as exceptionally well preserved, noting that "in soundness, no other example surpasses it" — a remarkable assessment for a sword more than seven hundred years old.

From Edo Castle to a Daimyō Family

This tantō has a documented provenance reaching back to the highest circles of Tokugawa-era power. White-paper labels with vermilion seals depicting a "diamond-leaf" crest, still affixed to the plain wooden storage scabbard, identify the blade as a former possession of the Yanagisawa family, lords of the Yamato Kōriyama domain.

The Yanagisawa family rose to prominence through Yanagisawa Yoshiyasu (1659–1714), a close attendant of Tokugawa Tsunayoshi, the fifth Tokugawa shogun. When Tsunayoshi entered Edo Castle as shogun in 1680, Yoshiyasu accompanied him as a trusted advisor and was eventually elevated to a daimyō with holdings exceeding 150,000 koku. The shogun visited the Yanagisawa residence on no fewer than fifty-eight occasions, and each visit was accompanied by gift exchanges that filled the Yanagisawa armory with magnificent swords.

Yoshiyasu's diary "Rakushidō Nenroku" records that on the twenty-second day of the third month of Genroku 4 (1691), when Tsunayoshi visited the Yanagisawa estate, he bestowed upon Yoshiyasu's eldest son Yasuteru (later renamed Yoshisato) "a Rai Kunitoshi short sword, eight sun one bu in length, with an appraisal certificate valuing it at twenty pieces of gold." Scholars at the Kurokawa Institute identify this entry as the origin record of the present blade. Listed in a 1924 Taishō-era auction catalog when treasures of the Yanagisawa house were dispersed, it eventually entered the Kurokawa collection.

Why It Was Designated a National Treasure

The tantō was first designated an Important Cultural Property on April 30, 1935, then elevated to the highest cultural rank — National Treasure — on November 14, 1953, under Japan's Cultural Properties Protection Law. Several factors justify this exceptional status.

First is the work's quality. As an authentic, signed example by Rai Kunitoshi at the height of his powers, it represents one of the pinnacles of Yamashiro-school swordmaking. The forged surface displays the tightly packed fine wood-grain pattern (ko-itame) prized by Kyoto smiths, the temper line is a luminous and crisp medium straight pattern with subtle variations including bright lines of activity called kinsuji at the cutting edge, and the small rounded boshi of the tip area glows softly. Connoisseurs describe such a blade as "akarui" — luminous.

Second is its remarkable state of preservation. The tang is original and untouched, retaining its original shape, file marks, and signature. The blade has not been shortened or re-tempered. After seven centuries, it remains essentially as Rai Kunitoshi made it.

Third is its historical importance. The unbroken chain of ownership from a Tokugawa shogun to a daimyō family to a modern foundation, documented by inscriptions, diary entries, and accompanying mountings, makes this not only a masterpiece of metalwork but an artifact of social and political history.

Highlights to Look For

When visitors stand before the blade in the institute's display case, several features reward careful observation:

• The luminous geometry of the temper line, where the polished metal of the cutting edge meets the misty surface of the body in a clean, bright boundary.
• The fine "ko-itame" wood-grain forging pattern, visible only when the light falls correctly across the polished surface.
• The carved goma-bashi grooves on one face — narrow parallel lines symbolizing the ritual sticks used in Buddhist fire ceremonies, reflecting the spiritual dimension of swordmaking in medieval Japan.
• The clear three-character signature "来国俊" cut into the tang in the smith's distinctive hand.

The blade is normally displayed together with its lavish accompanying mountings (koshirae). The hilt collar and other fittings are decorated with hollyhock crests, the heraldic emblem of the Tokugawa house, and the lacquered scabbard is finished in luxurious gold pear-skin (nashiji) ground scattered with aoi crests of varying sizes — a tour de force of the maki-e lacquerer's art.

The Kurokawa Institute and How to Visit

The Kurokawa Institute of Ancient Cultures was founded in 1950 by the Kurokawa family, three generations of Osaka-based financiers who built one of the finest private collections of East Asian art in Japan. The collection contains two National Treasures, sixteen Important Cultural Properties, and dozens of Important Art Objects, with Japanese swords forming its most celebrated category. The institute moved to its current Nishinomiya hillside location in 1974.

Two important practical points govern any visit. First, the institute opens to the public only twice a year, for approximately one month each in spring (mid-April through mid-May) and autumn (October through November), corresponding to its themed exhibitions. Outside these windows the doors remain closed. Second, whether the Rai Kunitoshi tantō is on display depends on the season's exhibition theme — visitors particularly interested in this blade should verify in advance through the institute's website or by telephone.

The institute lies on a steep hillside above Kurakuen, an upscale residential district. From Hankyū Shukugawa Station on the Kobe Line, take the Sakurayama-nami bus toward Yamaguchi and alight at Kayandō-chō, then walk roughly fifteen to twenty minutes uphill. A taxi from the same station takes about ten minutes. During exhibition weekends and national holidays, the institute operates a complimentary nine-seat shuttle car between Kurakuen-guchi Station and the institute, departing roughly every thirty minutes.

Things to See Nearby

The Kurakuen and Shukugawa districts of Nishinomiya offer rewards beyond the institute itself. Shukugawa Park, lined with hundreds of cherry trees, is one of the most celebrated hanami spots in the Kansai region during early April. The Nishinomiya Shrine, ancient guardian of the city and the head shrine of all Ebisu shrines in Japan, sits a short train ride away and is famous for its January "running men" festival in which worshippers race through the precinct to be acclaimed lucky men of the year.

Travelers with an appetite for sake should know that Nishinomiya forms part of the Nada-Gogō region — the most prestigious sake-brewing area in Japan — and several historic breweries near the coast welcome visitors for tastings and tours. For those drawn deeper into the world of Japanese swords, the Hayashibara Museum of Art in Okayama and the Tōken Museum in Tokyo's Ryōgoku district preserve other masterworks of the medieval smiths, while Kyoto, where Rai Kunitoshi himself worked, lies barely thirty minutes away by train.