Sixty years of war between two courts drove blades long and broad, and Osafune met the demand: Kanemitsu and Chōgi led forges serving the provincial warriors who did the fighting, while Sōshū influence arrived with the armies to create Sōden-Bizen.
With the adoption of the Soden-Bizen practice, various branches and sub-schools formed from the need to seek out greener pastures following the rise of the fledgling Soshu School. Branching from the Hatakeda derivatives, such as Motoshige, up to the Omiya School, which is believed to have sprouted from Kagemitsu’s peer, Chikakage, various sub-groups of the Osafune School came to be. Of these schools, the closest in style to earlier Bizen was the Ko-Sori School, of which a daito by its later smith, Moriyuki, will be assessed. The blade itself has a classical sugata, with a pronounced curve, slight funbari, and a gentle tip, echoing earlier works of the Kamakura Period, rather than the wider, more masculine shape seen in the period of the sword’s forging. The surface grain is composed of a looser itame-hada blended with interspersed mokume. The jiba is bright, primarily due to the sparkling ji-nie found throughout the blade. Looking toward the hamon, it is composed of a ko-gunome midare in ko-nie deki. Choji formations, however restrained, are also interspersed throughout the temper, adding a controlled chaos to the nioi guchi that mimics the nearby Ko-Yoshii School. Activity is highly present throughout the blade, including ashi of various sizes, kinsuji along the nioi guchi, and sunagashi, adding depth throughout each layer of the hamon. The temper is closely followed by a midare-utsuri up to the kissaki, where the hamon ends gently in an undulating ko-maru boshi with a slight kaeri turnback. With metallurgical details pointed out, relevant measurements are listed below. The nakago of the blade is ubu with a kuri-jiri tip, although machi-okuri has been performed to shorten the blade length. Along the tachi-omote, the naga-mei signature “Moriyuki of Osafune in Bishu”(備州長船守行) is delicately inscribed, falling in-line with other Osafune sub-branches. Three mekugi-ana have been punched into the tang, inferring a long history of alternating fittings with various conflicts and owners. The blade’s shape is in shinogi-zukuri, with an iori-mune. This is the most common shape associated with the Japanese sword, originating from the conception of the nihonto with the kenukigata-tachi and continuing up into the present day. By the time of this sword’s forging, various masters, including the Osafune School, of which Moriyuki descended, had gained mastery of this geometry, with Moriyuki himself continuing in these footsteps. This is reinforced by the smith foregoing the use of any elaborate horimono in this work, allowing the style of his forefathers to shine through in the steel itself. The blade is rated “Tokubetsu Hozon” by the NBTHK, implying a higher level of quality than is typically expected for a Japanese sword. This appraisal is a testament to the high-level craftsmanship of an excellent smith, alongside an acknowledgement of centuries of meticulous maintenance by custodians from all social classes and regions of Japan. The Ko-Sori School was formed from a minor exodus of the swordsmith Shigeyoshi, who studied under the grandmaster Kanemitsu, a swordsmith who studied under Masamune and brought his traditions to Osafune. There, the smith took on works inspired by the Sagami Tradition, eventually bringing on the age of “So-Den Bizen” works, which took close inspiration from the Soshu grandmasters. Following his tutelage of Shigeyoshi, the student eventually departed from the mainline Osafune School, opening up a local workshop along the Yoshii River. There, he took on new students, forming the Ko-Sori School, which he had named after his own personal name, Ko-Sori Kuzaemon, continuing up into the late Nanbokucho Period. This school often worked alongside both the mainline Osafune branch and the Omiya School, leading to great overlap between the Osafune-based Bizen masters. Most notably, this can be seen in the case of the “Oei San-Mitsu”, a set of three grandmasters of the early Muromachi Period, which are believed to have originated in either the Omiya or Ko-Sori branches of the Osafune School. Although definite conclusions are not possible in the modern day, Yasumitsu is often believed to be a Ko-Sori-based master, studying under the third-generation Shigeyoshi. Slightly before the time of Yasumitsu, Moriyuki gained prominence as the school’s final “official” grandmaster, operating from 1390 CE to 1394 CE. Due to their shared family line, Moriyuki is likely a sibling or cousin of Yasumitsu’s (indirectly through the merging of the Hatakeda Branch into the Ko-Sori School), continuing the Ko-Sori School until its eventual decline as the Osafune School consolidated, requiring greater manpower to produce large swathes of blades for the new armies that defined the conflict-ridden Muromachi Period. As such, this work stands as a final example of pre-war opulence from a more delicate line of the Osafune School. In addition, their proximity and similarity in workmanship to the Ko-Yoshii School open up new avenues of research, especially due to the possibility of influences from the Ichimonji School via continuous interactions between these two competitors, making this blade an odd transition not only between works of a peacetime and wartime economy, but also one between the classical style of the Ichimonji School and the more forward-thinking Osafune lineages. Article by Nicholas Zogu -Photographs from Charlie White’s Facebook page; Blade in Possession of Charlie White-
Offered by Tosa Touken Do
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Bizen-den · Bizen · around 1390-1394
Tōken Taikan top 37%
2 pieces on the market now
Bizen-den · Bizen
20 pieces on the market now
The Kozori (小反り) form a loose body of Bizen smiths who worked at and around Osafune in the closing decades of the Nanbokucho period and on into early Muromachi, and the NBTHK defines them less by descent than by exclusion: they are the late-Osafune hands who fall outside the specific lineages of Kanemitsu, Chogi, Motoshige and the Omiya group, gathered under one name as a convenience. The reading of the name itself has been explained in several ways, and the published sources are candid that it resists a clean definition; the prevailing sense is the ko-sori, the slight or shallow reverse-curvature of the blades, the shape running to a deep koshizori with marked funbari and a small point in the older pieces and growing heavy in the kasane toward Oei. The body has no single founder. Smiths such as Moromitsu (師光), recorded as the father of the Oei master Morimitsu, anchor the group through dated tachi; Iesuke and Iemori carry Hatakeda blood; Nariie descends from Kagehide; Morisuke, Shigeyoshi, Tsunehiro, Hidemitsu, Motomasa and others fill out the periphery, several of whose lines run several generations and whose precise generation-by-generation reading the institution leaves to further study. Across these hands runs a shared vocabulary, and the recurring word for it is scale. The jigane is the constant: an itame mixed with mokume and nagare, the grain standing a little (hada-tachi), fine ji-nie attaching, dark chikei-toned and at times jifu-like passages crossing the steel, and over it the midare-utsuri (sometimes a bo-utsuri or straight sugu-utsuri) that places the group squarely in the Bizen-den. The temper is nioi-based with ko-nie, built on a shallow ko-notare into which the smiths set ko-gunome running connected and threaded, pointed togariba, angular squared elements, open-waisted koshi-biraki gunome and modest choji, the whole kept small and crowded (kozumu), with ko-ashi and yo entering and fine sunagashi and kinsuji playing through. The boshi answers in midare-komi, pointing or settling to a ko-maru with hakikake.
Within the shared idiom each hand has its tell: Moromitsu tempers the most subdued, low-lying midare; Nariie's gunome crowds where Kanemitsu's opens; Hidemitsu and Hidemitsu of the Koreha branch lean to a reverse-slanting saka-gakari and saka-ashi near the Aoe manner, and turn now and then to a quiet chu-suguha; Tsunehiro favours a kataochi-like gunome; Iesuke and Iemori, working into Oei, open the valleys toward the early-Muromachi pattern. A collector seeks Kozori for legibility rather than flourish. Many of the best survivors are ubu, signed and dated tachi, and that dated file (Joji, Oan, Eiwa, Shitoku, Eitoku, Meitoku into Oei) gives the late history of Osafune a year-by-year spine, prized as reference material for the period; the names also map a province pulled between the Northern and Southern courts, Morisuke's Joji dates reading as Northern Court alignment. To kantei the group is to read it against its neighbours: the small, crowded, nioi-toned midare and the standing itame with kawarigane chikei separate it from the bolder, more uniform gunome of the Kanemitsu mainline of the Nanbokucho height, while the open koshi-biraki valleys and the heavier, sakizori late sugata point forward to and distinguish it from the more decorative Oei-Bizen of Morimitsu and Yasumitsu (a threshold several Kozori blades, in NBTHK phrasing, already anticipate). Among the members the institution ranks Moromitsu and Nariie high (Nariie held equal to the Kanemitsu pupil Masamitsu), Iesuke beside the leading Oei names, and Hidemitsu the leading hand of the Koreha branch. Provenance, though thinly recorded for some, reaches real houses: blades descend through the Kuroda, Kaga Maeda, Shonai Sakai and Hojo families, with examples in the Hayashibara Museum and the national museums, and the occasional Imperial line. A signed, dated Kozori blade comes to hand only from time to time, a quiet, datable window onto Osafune as it closed its Nanbokucho age. Learn more →
| Smith | Era | Designated |
|---|---|---|
| Hidemitsu秀光 | 1375-1392 | 19 |
| Iesuke家助 | 1394-1428 | 11 |
| Nariie成家 | 1352-1362 | 21 |
| Iemori家守 | 1377-1406 | 15 |
| Morisuke守助 | 1354-1384 | 7 |
Bizen in the Nanbokuchō period
Sixty years of war between two courts drove blades long and broad, and Osafune met the demand: Kanemitsu and Chōgi led forges serving the provincial warriors who did the fighting, while Sōshū influence arrived with the armies to create Sōden-Bizen.
A Hozon-certified blade judged to show notably superior workmanship and a better state of preservation. The bar is higher: re-tempered blades and most unsigned Muromachi/Edo works are excluded.
The NBTHK (Nihon Bijutsu Tōken Hozon Kyōkai, the Society for the Preservation of Japanese Art Swords) is a public-interest incorporated foundation founded in 1948 and supervised by Japan’s Agency for Cultural Affairs (Bunkachō); it is based at the Japanese Sword Museum in Tokyo. Its expert panels physically examine each submitted work (shinsa) and issue a certificate (kanteishō) ranking it by artistic and historical merit. NBTHK papers are the most widely recognized standard of authentication for Japanese swords and fittings.
NBTHK official siteAs a rule, we do not accept returns from overseas. Once a deposit is paid, we hold the item for up to 3 months. The deposit is non-refundable.
$10,000