Kantei
Old black-and-white photograph of a whole tachi and, above it, the tang enlarged, with five holes.

Swordsmith of Hakata (Chikuzen) · late Kamakura and Nanbokuchō

Samonji (左, Sa)

The swordsmith of Hakata who signed with a single character, 左 (Sa): master of the tantō, maker of the only signed tachi of his school and, according to tradition, a pupil of Masamune. His life, his style, his famous works and his sources

Samonji, or simply Sa, worked in Hakata, in Chikuzen Province (Kyūshū), between the end of the Kamakura period and the Nanbokuchō, and signed with a single character, 左 (Sa). Almost all his signed work is tantō; his only signed tachi, the Kōsetsu Samonji, is a National Treasure. Tradition counts him among the ten pupils of Masamune.

Association of Cultural Properties, Japan (1952), public domain, via Wikimedia Commons

Kamakura–Nanbokuchō
Period
3
Signed National Treasures (kokuhō)
1
Signed tachi that survive
25.4 cm
Blade of his largest tantō
On this page
  1. Quick profile
  2. In short

Quick profile

Name
Samonji or Sa; to tell him apart from the other swordsmiths of the school, 大左 (Ō-Sa, “the great Sa”) AT
Kanji and reading
左 (Sa) · 左文字 (Samonji) · 左衛門三郎 (Saemon Saburō), his common name · 源慶 (Genkei), his Buddhist name AT
Period
Late Kamakura and early Nanbokuchō, 14th century; no dated work is known AT
Province
Chikuzen (筑前, Chikuzen), in Kyūshū: Hakata, today in the city of Fukuoka HD
School
The Samonji school (左文字派, Samonji-ha), of which he is the head HD
Family
Son of 実阿 (Jitsua) and father of Sa Yasuyoshi (左安吉, Sa Yasuyoshi), both swordsmiths AT
Master
His father, Jitsua; tradition also makes him a pupil of Masamune AT
Signature
左 (Sa) and 筑州住 (Chikushū jū, “resident of Chikuzen”), on one or on both faces of the tang HD

In short

What we know. His blades signed 左 (Sa) and 筑州住 (Chikushū jū) are in Japan’s official databases of cultural properties: two of them, the tachi Kōsetsu Samonji and the tantō Taikō Samonji, are National Treasures, and others are Important Cultural Properties in the national museums of Kyoto and Kyūshū.

How we know it. His family, his names and his place in Hakata are given by the NBTHK, the national museums and the Japanese Wikipedia, which follow old treatises and tradition.

What we do not know. When he was born and when he died: there is no dated work of his. That he learned with Masamune is tradition, not a documented fact.

Sections

  1. Hakata · the lineage · Masamune Life and times His names, his family of swordsmiths, where the name “Samonji” comes from and what tradition says of his master.
  2. Tight itame · notare with nie · rising bōshi Work and style The kantei points of his work: the steel, the temper, the point, the shape, the tang and the signature.
  3. National Treasures · meibutsu Famous works The Kōsetsu, the Taikō, the Sayo and the Yoshimoto Samonji, and the tantō of the national museums.
  4. Works on display Videos The Kōsetsu Samonji at the Fukuyama Museum of Art and the audio guide of an exhibition of the school.
  5. Bibliography and credits Sources The sources consulted on 4 October 2026, with their link, and the credit for each image.