Kantei
A whole tachi, wide and curved, on a black background, with the tang on the left and a groove along the back.

Swordsmith of Osafune (Bizen) · Nanbokuchō

Chōgi (長義)

A smith of Osafune, in Bizen, of the Nanbokuchō period, a leading figure of Sōden-Bizen: his times, his work, his famous works, a video and his sources

Chōgi (長義, Chōgi), also read Nagayoshi, forged at Osafune, in Bizen province, during the Nanbokuchō period. He belongs to an Osafune branch distinct from the main one and is the central figure of Sōden-Bizen, which adds to the Bizen steel the nie and the broad tempers of Sagami: the Bizen smith who looks least like Bizen.

Tokyo National Museum, via ColBase

1350–1380
His dated blades, according to the NBTHK
1362
Dated tantō at the Tokyo National Museum
2
Signed tachi that are Important Cultural Properties
On this page
  1. Quick profile
  2. In short

Quick profile

Name
Chōgi or Nagayoshi AT
Kanji and reading
長義 (Chōgi, Nagayoshi); signature 備州長船住長義 (Bishū Osafune jū Chōgi) or 備前国長船住長義 (Bizen no Kuni Osafune jū Chōgi) HD
Period
Nanbokuchō, second half of the 14th century; the dates change from one source to another HD
Province
Bizen, at Osafune HD
School
Osafune, of the Sanenaga branch; Sōden-Bizen HD
Master and lineage
Son of 光長 (Mitsunaga) and grandson of 真長 (Sanenaga), according to the treatise Kokon Meizukushi; his elder brother was 長重 (Chōjū) AT
Documented fact and tradition
Documented: his signed and dated blades. Tradition: that he was one of the ten pupils of Masamune, which his dates do not allow. AT

In short

What we know. He signed and dated tantō and some tachi at Osafune for some thirty years in the second half of the 14th century. Almost all his long swords were shortened and lost their signature. Several of his works are Important Cultural Properties, among them the Honsaku Chōgi of the Tokugawa Art Museum.

How we know it. From his blades, the records of the State and of the national museums, and the studies of the NBTHK.

What we do not know. Who his master was, whether there were one or two generations, and whether he was ō-wazamono, which two articles of the same encyclopaedia affirm and deny.

Sections

  1. Osafune · Nanbokuchō · Masamune jūtetsu Life and times His lineage, his dates, the eras he dated with and the tradition that makes him a pupil of Masamune.
  2. Sōden-Bizen · mimigata · Chōgi-bōshi Work and style The kantei keys of his tachi and his tantō, and what they are confused with.
  3. Important Cultural Properties · meibutsu · museums Famous works The Honsaku Chōgi and its copy, his designated blades and those kept by the national museums.
  4. Tokugawa Art Museum Videos A trailer from the museum that keeps the Honsaku Chōgi.
  5. Bibliography and credits Sources The sources consulted on 4 October 2026, with their links, and the credit for each image.