Tanto (unsigned Masamune (famous Masamune Knife))

A Dagger Named After a Kitchen Knife

The blade measures just 23.9 centimeters, yet it is 3.5 centimeters wide at the base. Those proportions, broad and short with almost no curvature, reminded Edo-period connoisseurs of a kitchen knife, and so this dagger by the great swordsmith Masamune came to be called Hocho Masamune, the "Kitchen-Knife Masamune." Far from being an insult, the nickname appears in the Kyoho Meibutsu Cho, the official register of celebrated swords compiled by the Tokugawa shogunate in the early eighteenth century. Only the most storied blades in Japan earned a place in that book.

Today the dagger belongs to the Tokugawa Reimeikai Foundation and is kept at the Tokugawa Art Museum in Nagoya, the institution that preserves the heirlooms of the Owari Tokugawa family. The government designated it an Important Cultural Property on November 14, 1953, and elevated it to National Treasure on March 20, 1954.

Three daggers named Hocho Masamune survive. All three are National Treasures. This one, by the museum's own assessment, is the largest of the trio and shows the boldest patterning in its steel.

Masamune and the Soshu Tradition

Masamune worked in Kamakura, in Sagami Province (present-day Kanagawa Prefecture), in the late thirteenth and early fourteenth centuries. He is widely regarded as the finest swordsmith Japan ever produced. His achievement was the perfection of the Soshu tradition, a style of forging that combined steels of different hardness to create blades of remarkable toughness and, as a side effect, extraordinary visual drama. Crystalline particles called nie glitter across the surface, and bright lines known as kinsuji and inazuma (literally "lightning") streak through the hardened edge.

Masamune rarely signed his work. Daggers like this one were often shortened or left unsigned from the start, so attribution rests on the judgment of appraisers, above all the Hon'ami family, who served the shoguns as sword connoisseurs for generations. The official designation records this blade as mumei, unsigned, with the attribution to Masamune carried by centuries of expert consensus rather than an inscription. The tang survives in its original, unaltered form, shaped like a boat hull with a single peg hole.

Why It Became a National Treasure

The official description in the national cultural property database reads like a connoisseur's field notes. The blade is flat-forged (hira-zukuri) with a ridged back, thin in cross section, wide in body, and slightly curved. The steel shows a fine, tightly knit wood-grain pattern (ko-itame) with thick nie and a misty reflection called utsuri. The temper line undulates gently, then erupts near the point into large irregular patterns mixed with ear-shaped lobes, with patches of detached tempering that flicker above the edge like spilled fire.

What sets the dagger apart from every other Masamune, though, is the carving. A suken, the straight ritual sword associated with the Buddhist deity Fudo Myo-o, has been carved entirely through the blade as openwork. Light passes through the steel. The database calls this piercing technique "unparalleled," and claw-shaped motifs are carved on both faces as well. An inventory of Tokugawa Ieyasu's estate listed the piece as "Horinuki Masamune," the "carved-through Masamune," which suggests the openwork astonished people in the seventeenth century just as it does now.

Cutting a void into a blade only a few millimeters thick, without distorting it during forging and quenching, demanded control that few smiths in any era possessed.

From Ieyasu's Estate to Nagoya

The dagger belonged to Tokugawa Ieyasu, the founder of the Tokugawa shogunate. After his death in 1616, his enormous collection at Sunpu Castle was divided among his younger sons under a settlement known as the Sunpu Owakemono. This blade went to his ninth son, Yoshinao, the first lord of the Owari Tokugawa, the most senior of the three Tokugawa branch houses.

A broad, knife-like dagger suited neither formal gift exchange nor a lord's personal wear, and according to the museum the piece spent long years stored inside the keep of Nagoya Castle. That quiet history helps explain its condition. The blade has survived in unusually healthy state, its surface and edge largely as the smith left them seven centuries ago.

When the nineteenth head of the family, Tokugawa Yoshichika, established the Tokugawa Art Museum in 1935, the dagger entered the collection it remains in today, alongside more than 10,000 daimyo heirlooms that include the celebrated Tale of Genji illustrated scrolls.

What to Look For in the Gallery

Start with the silhouette. Most daggers of the Kamakura period are slender. This one is unmistakably squat and broad, and once you register the proportions the nickname needs no explanation.

Then move close and find the openwork sword carving. Depending on the lighting you may see the gallery wall through the blade. Check both faces for the small claw-shaped carvings that accompany it.

Give the steel itself time. The undulating temper line steadies along the lower body, then breaks into wild activity near the tip, exactly where a blade does its work. Tilt your head and the nie particles catch the light like frost. Fine bright lines run through the hardened edge; appraisers read these kinsuji and lightning streaks as Masamune's signature in everything but name.

One practical note: the museum rotates its displays, and no single object is guaranteed to be on view at any given time. The dagger appears in thematic exhibitions of the sword collection, which numbers more than 500 blades. Checking the exhibition schedule on the museum website before a visit is the safest course.

Visiting the Tokugawa Art Museum and Around

The museum stands in a quiet residential quarter of Nagoya's Higashi Ward, on land once occupied by an Owari Tokugawa retreat. From Nagoya Station, city bus route Kikan 2 reaches the Tokugawaen Shindeki stop in about thirty minutes, with a three-minute walk remaining. Alternatively, take the JR Chuo Line to Ozone Station and walk about fifteen minutes. Opening hours run from 10:00 to 17:00 (last entry 16:30), closed Mondays, with a holiday Monday pushing the closure to the next weekday. Admission was revised in April 2026 and varies by exhibition; adult tickets for special exhibitions are around 2,000 yen, so check the official site for current rates.

Plan time for Tokugawaen, the strolling garden directly beside the museum, where carp ponds and a waterfall compress the scenery of a daimyo estate into a city block. The adjoining Hosa Bunko library holds the books of the Owari Tokugawa, including volumes from Ieyasu's own collection. A short ride west brings you to Nagoya Castle, the fortress Ieyasu ordered built for Yoshinao, in whose keep this very dagger once rested. Seeing the castle and the blade on the same day connects the two halves of the story.