Kantei
A long blade without mounting, with a gilt habaki, on a white cloth in a museum display case.

Osafune (Bizen) · mid-Kamakura

Mitsutada (光忠)

The de facto founder of the Osafune school, in Bizen, in the mid-Kamakura: his period, his flamboyant chōji, his National Treasures, the Shokudaikiri and his sources

Mitsutada (光忠, Mitsutada) worked in Osafune (長船, Osafune), in Bizen Province, in the mid-Kamakura, and is held to be the de facto founder of the Osafune school, which produced smiths throughout the Middle Ages. He forged robust tachi with flamboyant chōji (丁子, chōji); some thirty blades survive, many shortened and none dated. Oda Nobunaga came to gather more than twenty.

SLIMHANNYA, CC BY-SA 4.0, via Wikimedia Commons

about 30
Surviving blades
3
National Treasures
more than 20
Oda Nobunaga’s Mitsutada
none
Dated blades
On this page
  1. Quick profile
  2. In short

Quick profile

Name
Mitsutada; Osafune Mitsutada; two-character signature, 光忠 (Mitsutada) AT
Kanji and reading
光忠 (Mitsutada) · 長船光忠 (Osafune Mitsutada) AT
Period
Mid-Kamakura, with three datings: 1247–1256, 1247–1278, and from about 1238 to the beginning of the Bun’ei era (1264–1275) AT
Province
Bizen (備前, Bizen): Osafune, in the Yoshii basin, today Setouchi (瀬戸内, Setouchi), in Okayama AT
School
Osafune (長船派, Osafune-ha), of which he is held to be the de facto founder HD
Master and family
Son, according to the old texts, of Chikatada (近忠, Chikatada), of whom no work survives; father of Nagamitsu (長光, Nagamitsu) AT
Documented fact and tradition
Documented: his blades in the museums and in the Agency for Cultural Affairs’ database, among them National Treasures and Important Cultural Properties. Tradition: his dates, his father Chikatada and the story of the Shokudaikiri. HD

In short

What we know. The Tokyo National Museum has him living in Osafune in the mid-Kamakura and calls him the de facto founder of the Osafune school. The Agency for Cultural Affairs’ database records his signed and attributed blades, and when it was consulted on 4 October 2026 two of them were National Treasures.

How we know it. From the museum records (ColBase, e-Museum) and those of Bunka Isan Online, and from the NBTHK Sword Journal; and, for his dates and his story, from the Japanese Wikipedia, the Kotobank dictionaries and Markus Sesko.

What we do not know. His exact years: there is no dated blade of his. Whether any is in the Kyōhō meibutsuchō, and the official records of the blades of the Izumo, Itsukushima and Kishū shrines.

Sections

  1. Chikatada · Osafune · Nobunaga Life and times The de facto founder of Osafune, three datings, the debate on the origin of the school and Oda Nobunaga’s Mitsutada.
  2. Chōji · midare-utsuri · ikubi-kissaki Work and style His kantei keys, from the sugata to the nakago, and what sets him apart from the Ichimonji school.
  3. National Treasures · Ikoma · Shokudaikiri Famous works His National Treasures and Important Cultural Properties, the Ikoma Mitsutada and the Shokudaikiri, burnt in 1923.
  4. Press · Osafune today Videos The Shokudaikiri in Mito, in the local press, and the Osafune tradition told by the Setouchi city council and Okayama Prefecture.
  5. Bibliography and credits Sources The sources consulted on 4 October 2026, with their links, and the credit for each image.