Kotetsu, Tsuda Sukehiro, and the 2026 Japanese Sword Museum exhibition

From 24 October through 20 December 2026 the Japanese Sword Museum in Sumida shares a show with the Fukuyama Museum of Art in Hiroshima. The title is 新刀・東西の巨匠 虎徹と助広: master smiths of east and west in the shinto, or new-sword, period, Nagasone Kotetsu and Tsuda Sukehiro. The schedule is Saturday the 24th through Sunday the 20th. Hours are 9:30-17:00, last admission 16:30.

The schedule page centers those two smiths and had not published a blade-by-blade list. Which swords travel from Fukuyama stays off that page, so check touken.or.jp again before you travel. The Suzuki collection ends 12 October 2026. This show opens on the 24th. While exhibitions change, and over New Year, the building can be shut. A ticket for 18 October can meet a locked door.

The Edo pair, after the old schools

The famous swordsmiths page is Masamune, Muramasa, Bizen, and the Gokaden. This page is the Edo pair. Kotetsu worked in Edo. Sukehiro worked in Osaka.

Shinto (新刀) means new sword, the smithing after about 1596. Koto (古刀) is old sword, the work of Masamune's era. English uses that same spelling for the Shinto religion. On a blade label, shinto is a date band.

After the early seventeenth century the big battles thinned. A samurai still wore a katana as a sidearm and a status object, and he had time to look at a hamon in a room the way he looked at a painting. The sword-making page is how that line gets quenched.

Kotetsu in Edo

Nagasone Kotetsu's personal name was Okisato. Kotetsu is the name he used after he became a monk, a nyudo. The career note is NBTHK Sword Journal 707, December 2015. He had worked as an armorer, a katchushi, in Echizen. Around the Shoo era (1652-1655) he moved to Edo and took up swords. An early dated sword is March of Meireki 2 (1656). The last dated signature in that note is Enpo 5 (1677). About twenty years.

Some signatures say he was "half of 100," about 50, while living in Edo. The journal's current reading takes that as middle age, and it stops short of a birth year. His teacher is said to have been Kazusanosuke Kaneshige, and he later settled in Shitaya, according to a Tokyo Fuji Art Museum summary.

The steel is often tight ko-itame, with nie in a shallow notare mixed with gunome. That hamon is a low uneven line. A suguha next to it is the calm one. The crashing waves belong to Sukehiro. Because the name was copied constantly, a mei that reads Kotetsu is a claim. Papers, the shape of the nakago, the yasurime, and the steel do the rest.

Sukehiro in Osaka

Tsuda Echizen no Kami Sukehiro, the second Sukehiro, is an Osaka shinto smith, born Kan'ei 14 (1637) in Uchide village, Settsu, today's Ashiya area. Common name Jinnojo. Where an older website disagrees, this page follows NBTHK Sword Journal 827, December 2025.

Myotokuji temple records in Osaka support a father-and-son link with the first Sukehiro, called Soboro. Modern writing sometimes calls the second Sukehiro adopted. Edo-period sword books do not put it that way. The journal's current lean is father and son.

From changes in the signature, the journal puts the title Echizen no Kami around Manji 1 (1658), when he was about 22. An older site says 1657. Use 1658 as the NBTHK's current reading. The year is argued from how he signed. It is not a grant date this page has seen written out on one document.

In Kanbun 7 (1667), age about 31, he entered the service of Osaka castellan Aoyama Inba no Kami Munetoshi and took the family name Tsuda. Date-writing and file marks changed that same year. The NBTHK calls 1667 a turning year. He signed Tsuda in block script, kaku-tsuda, until about Enpo 2 (1674), then in cursive, maru-tsuda. Block strokes stay separate. Cursive joins them. On a photo of a tang, a beginner can learn that difference. The steel still has to agree.

Waves, and one blade measured

Early hamon followed his teacher's choji midare, clove-shaped bumps in an irregular line, then a larger gunome. Around Enpo 4 (1676) he made toran midare, also called toranba: rows of breaking waves, with bright spots some descriptions call tama. The pattern was widely copied. He was also very good at a quieter suguha of about five gentle waves, often wider just under the yokote, the line where the point begins. The katana parts page names that line.

Journal 827 measures one blade, dated Enpo 7 (1679), owned by the NBTHK: 2 shaku 3 sun 3 bu 3 rin, converted as 70.7 cm, sori 1.35 cm. One sword. A shaku is about 30.3 cm. A sun is a tenth of that, about 3.03 cm. A bu is a tenth of a sun, about 0.3 cm. A rin is a tenth of a bu, about 0.03 cm. Two shaku is about 60.6 cm and three sun about 9.1 cm. The bu and rin finish the journal's 70.7. On this length, 1.35 cm of curve is a shallow bow.

A blade near 70 cm is a katana, long enough for two hands, and shorter than an odachi. A wakizashi is often under 60 cm, so 70.7 cm has left that shorter sword. Later smith lists put his death in 1682, about age 46. The journal passage used here does not give that date, and this page is not quoting a tomb inscription. Dated work runs through at least 1679.

East and west on one table

Jihada and nie are the steel. Suguha, notare, gunome, and toranba are the line. Nakago, mei, and the two Tsuda scripts are the tang.

Why the prices sit so high

Few signed, healthy blades by these two exist next to the copies. The nakago has to stay ubu, unshortened, or a suriage cut can take the mei with the steel that was thrown away. A past owner sometimes shortened a long tachi into a katana, and the name went with the discarded steel.

Hozon means worthy of preservation, tokubetsu hozon especially worthy, juyo token important sword. Those are NBTHK opinions about authenticity and quality. A paper raises confidence, and the price follows. Committees revise attributions. Important Cultural Property and National Treasure come from the Agency for Cultural Affairs, and they are much rarer than a paper.

A blade at Important Cultural Property rank cannot be sold abroad in the ordinary way, so that scarcity stays in Japan. This is a description of the usual paperwork. A buyer in Japan needs the torokusho, the registration card, to own a real sword. A foreign buyer needs an export permit.

Rust pits, a tired polish, or a cracked hamon move the price as much as the name. The armor collecting page makes the same point for lacquer. Comparing two Kotetsu listings, ask who papered the blade, whether the tang is ubu, and whether the hamon matches his habit. The word genuine on a website does not answer those questions.

Hours, the walk, and the ticket

The English home page gives the address as 1-12-9 Yokoami, Sumida-ku, Tokyo 130-0015, with the hours and the Monday rule. The museum is at Ryogoku Station in Sumida. Visitor guides usually put the walk from the JR Sobu Line west exit at about 7 minutes. Use the museum map for the turns. Closed Mondays. If Monday is a national holiday, it opens Monday and closes Tuesday. In this run, 23 November 2026 is a Monday and Labor Thanksgiving Day, so the printed rule would close Tuesday the 24th. Confirm that week. The building can also be shut between shows and over New Year.

Ordinary adult admission has been listed at 1,000 yen. An October 2026 visitor guide listed 1,500 yen for this special exhibition, students 500 yen, under 15 free, groups of 20 at 1,200 yen. The special-show price was reported above the ordinary ticket. Confirm the figure on touken.or.jp. A higher fee usually pays for loans, insurance, and a shorter run. You are buying this checklist, rather than time in the permanent room.

On a listing, before you ever reach Sumida:

• Who issued any NBTHK paper, and at which level.
• Whether the nakago is ubu or the mei was lost in a suriage cut.
• Whether the hamon is a low line, toranba, or a quiet suguha.
• If the signature says Tsuda, whether the strokes are block or cursive.

On the day:

1. Recheck the gap after 12 October, and any Tuesday that follows a Monday holiday.
2. Pay whatever price the museum site prints for this show that week.
3. If a blade list has appeared, choose one sword and stay with the label.
4. Walk from Ryogoku Station with the museum map.

Questions people bring to the case