Kantei
A polished tantō without mounting, on a black background: an undulating temper line along the edge and a long engraving, ending in a point, along the back.

Sagami · Nanbokuchō · Sōshū-den

Akihiro (秋広)

A swordsmith of Sagami of the Nanbokuchō period, of the Sōshū tradition, who dated his blades from 1357 to the end of the 14th century: his times, his work, his famous works and his sources

Akihiro (秋広, Akihiro), who signed 相州住秋広 (Sōshū-jū Akihiro), is, with Hiromitsu, the great name of the Sagami forge in the Nanbokuchō period, the generation that followed Masamune and Sadamune. Unlike them, he dated his blades: the known ones run from 1357 to 1387 according to the NBTHK, or to 1392 according to the Kyoto National Museum. He is associated, with Hiromitsu, with the hitatsura temper. Nothing more is known of his life.

Kyoto National Museum, via ColBase

1357
First dated blade (Enbun 2)
1387
Last, according to the NBTHK (Shitoku 4)
1392
Last, according to the Kyoto National Museum (Meitoku 3)
2
Important Cultural Properties
On this page
  1. Quick profile
  2. In short

Quick profile

Name
Akihiro; signed 相州住秋広 (Sōshū-jū Akihiro); the name is also written 秋廣 (Akihiro) HD
Kanji and reading
秋広 (Akihiro) · 秋廣 (Akihiro) HD
Period
Nanbokuchō (南北朝, Nanbokuchō), 14th century: blades dated from 1357 to 1387, or to 1392 HD
Province
Sagami (相模, Sagami), which the signature abbreviates as 相州 (Sōshū) HD
School
The Sōshū tradition (相州伝, Sōshū-den), that of Masamune and Sadamune AT
Master and generations
His master is not known; some sources speak of a second generation, without academic backing PC
Documented fact and tradition
Documented: his dated blades, his signature and his designated works. Attributed: that with Hiromitsu he created hitatsura, and his place among the heirs of Masamune. II

In short

What we know. His signed and dated blades, from 1357 onwards; a tantō of 1376 in the Kyoto National Museum and an unsigned katana attributed to him, both Important Cultural Properties (重要文化財, jūyō bunkazai); a tantō of 1370 in the Tokyo National Museum, and a wakizashi of 1398 that is 重要刀剣 (jūyō tōken) and today belongs to the NBTHK.

How we know it. From the records of the national museums and of the official heritage database, and from the NBTHK’s 2026 study of him and Hiromitsu. His place in history is given by those same sources and by the encyclopaedias.

What we do not know. His master, when he was born and died, exactly where in Sagami he forged and whether there was a second generation with his name.

Sections

  1. After Masamune · alongside Hiromitsu Life and times What his dates, his signature and his place in the Sagami forge tell us.
  2. Hitatsura · engravings · short blades Work and style The keys to recognising his work: shape, steel, temper, point, engravings, tang and signature.
  3. Important Cultural Properties · museums Famous works His designated works and those held by museums, with the 1376 tantō of the Kyoto National Museum.
  4. Bibliography and credits Sources The sources consulted on 4 October 2026, with their link, and the credit for each image.