Yamato Hosho Katana

Yamato Hosho

periodLate Kamakura (ca. 1320)
designationNBTHK Juyo Token Katana
ratingJo-jo saku
nakagoo-suriage, mumei
nagasa71.2 cm
sori1.5 cm
motohaba2.85 cm
sakihaba1.8 cm
kissaki2.3 cm
nakago nagasa20.2 cm
nakago sori0.15 cm
price -sold-

The Jitetsu will be extremely fine with the Masame Hada showing very distinctly. The Masame Hada of Hosho blades are considered to be representative of the Yamato masame hada.

The masame hada will be made uniform from the machi all the way into the boshi, making the turn at the yokote into the kissaki in the line along the curve and it will run-out into the mune. Many of the blades which have been over polished will have hada ware, though this tendency is not necessarily confined to the over polished blades. The masame line, though it runs the length of the blade, does not run in a straight line but in a large wavy line. This is called HOSHO MASAME HADA.Albert Yamanaka, Nihonto Newsletters

The Yamato tradition is generally broken down into five schools, Senjuin, Taima, Shikkake, Hosho and Tegai.

The Hosho school was located in Takaichi-gori (Takaichi-gun) of Yamato province. This school is unique in these in that their name is not coming from an association with a temple, but is a family name recorded on one of the swords by Hosho Sadamune 保昌貞宗 in the Kamakura period. The only extant example of this mei however is not reliable, so we have only old oshigata to go on for this smith. Old books actually refer to Hosho Kunimitsu as the founder, but his blades are not found today.

The Yamato tradition as a whole is generally conservative, and the Hosho school is noted both as particularly conservative even among the five schools of Yamato. This means that the style and shape did not change much with the times, and distinguishing between individual smiths is very difficult. As such most blades take an attribution simply to Hosho as a school rather than to individuals smiths.

The Nihonto Koza refers to the confusion around the founding of this ha, saying that Hosho Kunimitsu is the same person as Hosho Sadamitsu, and that in one account Kunimitsu is the father of Sadayoshi who is the father of Sadamune. In another, Sadayoshi and Sadamune are brothers, both sons of Kunimitsu. There are dates on existing works by these smiths, Sadayoshi having a date of 1317 and Sadamune having a date of 1318. Both Sadayoshi and Sadamune are referred to with the nickname Hosho Goro indicating that they were also lay priests.

Detail of Juyo Yamato Hosho Katana

The Nihonto Koza refers to a sword with a signature of Sadatsugu 貞繼 that:

... shows the highest degree of technical skill, has one level more of an antique tone than the works of both Sadayoshi and Sadamune, and this impression is especially strong in the mei style. However, the fact that this name is omitted from the usual meijin and meikan books is strange.

Since the time of that writing, the blade became Juyo Bunkazai. Dr. Honma was of the belief that this was one of the Hosho founders if not the founder as the work was so good and looked older than other Hosho blades. If so then the school may date earlier than thought as the maker was omitted from the Meikan and not based on skill.

Lovers of Yamato swords learn to accept these kinds of open questions in the history of this tradition, as so few signed pieces exist and mysteries continue to abound.

One thing that is clear is that the traits of Yamato swords are something that everyone encounters very quickly in sword study. Not very much is written about Yamato, but we always hear the mantra of high shinogi, wide shinogi-ji, yakizume boshi, few signatures, hotsure in the nie hamon, and masame hada.

Among the school’s work, some blades have dense nie from the edge up to the inside of the habuchi; the hamon is bright and clear; there are frequent kinsuji and sunagashi; and the boshi has frequent hakikake. There is abundant hataraki. Other work from this school shows narrow bands of nie, less kinsuji, sunagashi and hakikake, and are somewhat gentle looking.

Because of their unique entirely masame jihada, the Hosho school name is famous, but there are very few swords extant today. These include tachi and tanto with signatures, katana without signature. These blades have classifications of Kokuho, Juyo Bunkazai, Juyo Bijutsuhin, Tokubetsu Juyo, and Juyo Token. The number of signed blades is 23, and the number of clearly identified works without a signature is around 45. Thus we do not have many chances to see work from this school today. [Note: this is from an older document, another 30 or so blades have been established.] NBTHK Token Bijutsu

As one studies deeper into Yamato, it becomes evident that masame is not very frequent at all as a form of construction in these schools, but that it shows up as a flavoring in the itame and mokume that is the actual basis of construction of Yamato swords. Han Bing Siong made a point of counting how many Juyo Token he could find from the various Yamato schools that were produced in pure masame.

  1. Shikkake: 5 masame out of 82
  2. Senjuin: 3 masame of of 80
  3. Taima: 2 masame out of 159
  4. Tegai: 1 masame out of 48

This gives a very clear conclusion that the diagrams encountered in the references that pound home the association of pure masame with Yamato are not so accurate. What is true though is that the Hosho school specialized in masame, and it is the presence of masame in this school that is the source of these diagrams above.

Detail of Juyo Yamato Hosho Katana

The Hosho school demonstrates a very unique workmanship in Yamato Province and is differentiated from other four major schools of Yamato Province. That is to say, the jihada is well-forged and pure masame-hada. The grain of the masame in the boshi area goes through to the mune line and the one in the bottom to the fine edge. Also open hada called tate-ware are seen in places and hamon is tempered on the basis of sugu-ha then hotsure, kuichigai, uchinoke and niju-ba are seen, and boshi becomes yaki-tsume with hakikake (the hamon tend to be wide in the boshi area). In addition, their blade has thick kasane and nakago has kiri tip and higaki-yasuri. NBTHK Token Bijutsu

Detail of Juyo Yamato Hosho Katana

Construction in masame is very difficult, as the welds form very long seams that take great skill to make perfect. As such, most blades in masame show ware along the welding lines. For the Hosho school these masa ware are not considered flaws, but are considered a kantei point and a hallmark of the school.

Hosho Tokubetsu Juyo Example
Hosho Tokubetsu Juyo Example

In [the Hosho school works], there are many which have tate-ware, but this is not objectionable, as been the case since olden times in other works. Nihonto Koza

The Hosho school marked their nakago with the higaki style of yasurime. Their tachi have shallow kurijiri tips, but their tanto have the kiri or the straight-across end cut. The Hosho school is characterized with a most distinct type of workmanship producing neat and uniform masame grain.

The smiths from this school all included the letter SADA to name themselves Sadayoshi, Sadamune, Sadaoki, Sadakiyo, and so on. It is not to exclude the other four Yamato schools as possible producers of perfect masame grain in the ji, but such perfectly masame structure blades are exceedingly rare among their examples, although almost all of them contain some straight grain in the kitae. NBTHK English Token Bijutsu

Detail of Juyo Yamato Hosho Katana

Anyone can draw a wavy line and it is impossible to tell within those patterns of waves what is intentional and what is jitter. In the same way any attempt to draw a perfectly straight line betrays the artist because any deviation from perfection stands out immediately. In this way excellent suguba is hard to form and as well, perfect masame has the same issue. Given that these are indirect or blind processes, achieving excellence in masame and suguba is something that reveals the skill of the artist.

Masa-ware are side effects of this process as the folding in itame and mokume naturally limits flaws. Straight grain is harder to weld and more subject to displaying these flaws and we do see this on Hosho blades even of the highest caliber. All of this difficulty may be why so few other smiths even attempted masame and is potentially a pride item in Hosho deciding to specialize in them. This blade does have one in the monouchi area, but due to its construction we forgive these in Hosho works. This is attested to by Tanobe Michihiro sensei as follows:

Even though Hosho's works often show tate-ware (vertical crease) in the masame, it has traditionally been positively recognized as a unique trait of their forging, and has never been counted as a fault. Tanobe Michihiro, retired head researcher, NBTHK

This treatment goes back to the old book Kuchisai Hidensho which refers to a course texture in these Hosho works and says that it looks like horse hair scattered about the blade. The Hidansho also notes that there is tate-ware in the works of this school and similarly says it is not objectionable in Hosho blades.

The top works of the Hosho school rapidly fade away with the Nambokucho period, though it is thought that some works of the Muromachi period are by descendants of this school though the Muromachi period in Yamato province was dominated by the Sue-Tegai smiths.

It is very difficult to single out a smith from them as their workmanships have close similarity but it may possible to do it from sugata. Sadayoshi normally makes tanto with around 27 cm. in ha-watari, a little wide mi-haba and extended ha-watari. Sadakiyo makes tanto with extend ha-watari between 27 and short ha-watari between 30 cm. also 21 and 24 cm. NBTHK Token Bijutsu

Detail of Juyo Yamato Hosho Katana
Hosho Masame Hada
Hosho Masame Hada

There are only a handful of known smiths of this school, Sadayoshi, Sadamune, Sadaoki, Sadamitsu, Sadazane, Sadakiyo, Sadayuki, Sadatsugu and Sadasue. Fujishiro gives the two possible founders a uniform rating of Jo-jo saku, and the students all Jo-saku for superior workmanship. My feeling is that with little material to judge, the grades here have a degree of estimation to them. This is confirmed by Fujishiro's notes all being extremely brief in regards to the Hosho smiths. In contrast, Dr. Tokuno assigns Hosho Sadakiyo a high score of 900 man yen in his rating in the Toko Taikan, making him very valuable, on a par with Ryumon Nobuyoshi (Jo-jo saku) and other Jo-jo saku smiths.

Among signed pieces known today there are the following signatures:

  1. Fujiwara Sadayoshi: 1
  2. Takaichi ju ~ Kingoto Sadayoshi: 2
  3. Takaichi ju ~ Kingoto Sadayoshi Saku: 1
  4. Washu Takaichi Kingoto Sadayoshi: 1
  5. Yamato Kuni Takaichi (cut off): 1
  6. Yamato Kuni Takaichi-gun Junin Saemon-jo Sadayoshi: 2
  7. Yamato Kuni Takaichi ju ~ Kingoto Sadayoshi: 1
  8. Sada~ (Unknown): 1
  9. Sadatsugu: 1
  10. Sadakiyo: 3
  11. Fujiwara Sadakiyo: 4
  12. Sadaoki: 2
  13. Fujiwara Sadaoki: 2
  14. Yamato Kuni Fujiwara Sadaoki: 1
  15. Yamato Kuni ju Fujiwara Sadamitsu: 2
  16. Hosho Sadamune Saku: 1

One note here is that the Hosho Sadamune is Jubi and is not currently regarded as valid. From the rest it can be seen that the Hosho smiths did not use Hosho in their signatures but preferred the clan name Fujiwara. This list is comprised of Juyo, Tokuju, Jubi, Jubun and Kokuho blades. So overall we can see that signed Hosho pieces are extremely rare.

Detail of Juyo Yamato Hosho Katana

Incidentally, it is an interesting feature of the Hosho school that when these smiths signed their tanto they signed very close to the machi. This was handed down through all of the smiths of the Hosho school it seems. This is not noted in any books but is something I've picked up on by studying oshigata. Examples of Sadayoshi, Sadakiyo, Sadamitsu and Sadaoki with long mei all exhibit this same trait. Because they signed so close to the machi the first character was in position to get polished down by the end part of the polisher's stroke. As a result, when signing with a long mei, the first character of the signature tends to be ground away and lost to polish. So we can take this as a kantei point that helps to validate a Hosho signature on a tanto, as if it is a long mei (anything more than two characters) we should expect to see the first character lost or at least damaged by way of polish. This is interesting as well because it confirms the strict nature of Hosho works, in that they were instructed in a method for signing tanto and each of the smiths adhered closely to it, along with every other step of manufacture of blades.

Additionally this method also invalidates the Hosho Sadamune Jubi tanto listed above because it is signed well below the machi and doesn't show any abuse of the first character as a result. The blade though is most likely authentic Hosho as the construction is correct, but it was probably made as a mumei, and the signature and horimono added at a later date to jazz it up.

Chikara Yoritoshi Ason presents a Tachi by Rai Kunitoshi and a Tachi by Bizen Sukekane to Dainagon in appreciation for being allowed to carry on the hereditary fief [of his family].

Also, as the legacy of Chunagon Tsunaari, presents a Katana by Masamune to the Shogun and a Katana by Sadamune to Dainagon. He then receives a Katana by Hosho Goro (Sadamune) from the Shogun himself for having supervised the building of the mausoleum of Keisho-In. Tokugawa Jikki, November 28th, 1705

Overall the NBTHK has authorized 71 Hosho only at Juyo and higher. Two of these are tachi, 37 are Katana, 6 are wakizashi and the remaining 26 are tanto. There are another 5 are Juyo Bijutsuhin, 3 are Juyo Bunkazai and one Kokuho. The Kokuho blade is the Meibutsu Kuwayama Hosho that was owned by the Maeda daimyo. The Hosakawa, Matsudaira, Date, Yamanouchi daimyo also owned Hosho on the list above as well as the Tokugawa Shoguns themselves. The Tokugawa Shoguns received Hosho as gifts and gave them as well to favored daimyo and retainers indicating that the admiration for this school extended to the highest level of Edo period society.

Detail of Juyo Yamato Hosho KatanaKoshirae Left
Juyo Token Yamato Hosho KatanaYamato Hosho Katana TsubaYamato Hosho Katana Kogai Origami

Juyo Token Yamato Hosho Katana

If you wanted a representative blade of the Yamato tradition in your collection, this is the one you should get. When we read about the Yamato tradition, all of the features that are held to be typical for this tradition are concentrated in the style of the Hosho school. As noted any time Hosho is brought up, this school is the most distinctive among all of the Yamato schools and stands as the archetype for the entire tradition though so few works remain to us.

This blade is very healthy, with a bright hamon and shows off all of the features one can wish for in a Hosho school blade. The jihada is a very finely forged masame that is mixed with a lot of ji nie and chikei and present from ha to the shinogi-ji. There are thick nie in the hamon that break into areas of hotsure and many small activities throughout. The blade has some of the typical tate-ware that we find in Hosho blades, but these are present all the way though to the Kokuho level and it is not to be taken as a detriment in judging Hosho works as all of the experts have stated above. They are found on all Hosho blades.

This blade with its tight, skillful forging is from the earlier parts of the Hosho school, though the conservative nature of this school means that the late Kamakura style held through to the early part of the Nanbokucho without much changing. This can make it hard to date Hosho works. The shape though is late Kamakura with a small side chu-kissaki according to the NBTHK. This is really a ko-kissaki however, as at 2.3 cm it is smaller than many kissaki on Heian blades that are described as such at 2.4. It has a deep koshi-zori curve that is both elegant and beautiful and makes it very easy to see that it is a Kamakura sword. There is some nie utsuri that follows the line of the shinogi.

The nakago of this blade is interesting as I think the bottom hole is the original one and most of the nakago is the original from when it was a tachi. The patina is very old and the yasurime have been consumed over the centuries which also corresponds to a great age. When this was made suriage rather than refile the nakago, it seems that a punch was used to create surface texture. This technique is a variation on tsuchime where the nakago is hammered to create a surface texture. All of these finishing techniques have a single goal, which is to provide an irregular surface which will provide friction and extra surface area when making contact with the wood inside a tsuka which is what gives a solid mechanical bond and keeps the sword seated in the tsuka.

There is a scar on the nakago just below the second hole from the top where the tsuba wore against the blade. When the tsuba and machi were in this position the blade would have been about 80 cm. On the katana omote at the very end of the nakago there appears to be the remnants of a character. I'm not sure if it's my imagination or not as there is not a lot to go on.

This blade passed Juyo very recently in session 64 and it did so in a slightly rusty condition and old polish. I chose to do a shiage to resolve the rust when it came to me, rather than a full polish, as I prefer to preserve whenever possible. A a result some small rust pits remain but they do not detract from the overall beauty of the blade. This Hosho blade stands with peer level quality to those that have passed Tokubetsu Juyo. The NBTHK pointed out several times in the setsumei that follows that the forging is excellent, and took pause at the end to so that in this blade the forging is particularly dense and well made, making it outstanding for a Hosho work. They also made note of the hamon being bright and clear, which are hallmarks of a blade in excellent condition as well as of a high quality craftsmanship.


I have added a very high quality koshirae to this blade with kiri-mon on waves tosogu that I think are Goto school. There is no paper to this koshirae other than for the kogai. The kogai just received Hozon papers to the Kaga Kinko group. You can read more about this group on my Kaga Kinko Tsuba listing. This group are all branches from the mainline Goto family so it agrees with my assessment on the koshirae.

Together they make for a beautiful set which can be displayed and appreciated in a collection of any level, especially for someone who is interested in a fine quality Yamato example.

Yamato Hosho Katana OshigataYamato Hosho Katana Origami

Juyo Token Katana

Appointed on the 6th of November, 2018 (Session 64)

Katana, Mumei, Yamato Hosho


shinogi-zukuri, iori-mune, normal mihaba, noticeable taper, wide shinogi-ji, high shinogi, despite the suriage a koshizori, chū-kissaki


dense and excellently forged masame that is mixed with some gently undulating nagare and that features plenty of ji-nie and much fine chikei


nie-laden suguha that is bright and clear and that is mixed with ko-chōji, ko-gunome, many ko-ashi, some hotsure, and fine kinsuji and sunagashi


sugu and running out as yakitsume


ō-suriage, kirijiri, yasurime indiscernible, three mekugi-ana, mumei


From existing signed Hoshō works we known that the school was located in the Takaichi district (高市郡) of Yamato province. The school flourished from the end of the Kamakura to the Nanbokuchō period and its most representative and well-known smiths were Sadamune (貞宗) and Sadayoshi (貞吉). Also highly skilled were Sadakiyo (貞清), Sadaoki (貞興), and Sadamitsu (貞光) and so we learn that the Hoshō smiths shared the character for Sada (貞). The workmanship of this school is the most unique of all of the five major Yamato schools and is characterized, i.a., by a jigane in pure masame and a nakago that is finished with higaki-yasurime.

This blade shows a dense and excellently forged masame that is mixed with a gently undulating nagare and that features plenty of ji-nie and much fine chikei. The hamon is a nie-laden, bright and clear suguha that is mixed with ko-chōji, ko-gunome, some hotsure, many ko-ashi and fine kinsuji and sunagashi. Thus, we recognize in the jiba the characteristic Hoshō features and we are in agreement with the period attribution to this school. The masame-hada is particularly well and densely forged and the ha shows a particularly prominent, bright, and clear nioiguchi for a Hoshō work, underlining so the excellent deki of this blade.

Yamato Hosho Katana Sayagaki


This sword bears an extensive inscription (sayagaki) by Tanobe Michihiro sensei. He is the retired former head researcher of the Nippon Bijutsu Token Hozon Kyokai (NBTHK). It is done in two parts as the first sayagaki was done before Juyo, and a note was added after Juyo.

  1. 和刕保昌
    Washu Hosho
  2. 大磨上無銘也
    Ō-suriage mumei nari.
    This blade is shortened and unsigned.
  3. 大和ニ一般的ナ鎬幅廣ク鎬筋高キ形状ヲ示ス大和五派中ニアリ個性的ナル総柾目鍛ヲ見セ穏健ナル小沸出来ノ直刃ヲ焼キ帽子焼詰メルナド同派ノ特色ガ明示サレシ優品也
    Yamato ni ippan-teki na shinogi-haba hiroku shinogi-suji takaki jōtai o shimesu Yamato-goha-chū ni ari kosei-teki naru sō masame-gitae o mise onken naru ko-nie-deki no suguha o yaki bōshi yakitsume narudo dōha ni tokushoku ga meiji-sareshi yūhin nari.
    It has a shape typical for Yamato, showing a wide shinogi-ji and a high shinogi. With its forging in pure masame, its hardening in a quiet suguha in ko-nie-deki, and its yakitsume-bōshi, we have here a masterwork that clearly shows within the Five Yamato Schools the characteristic features of the Hoshō School.
  4. 長弐尺参寸五分弱有之
    Nagasa ni-shaku san-sun go-bun chaku kore ari.
    Blade length ~ 71.2 cm
  5. 時在戊戌年梅見月探山識「花押」
    Jizai tsuchinoe-inudoshi umemizuki Tanzan shirusu + kaō
    Written by Tanzan (Tanobe Michihiro) in February of the year of the dog of this era (2018) + monogram
  6. 尚本刀ハ平成卅年十月第六十四回重要刀剣ニ指定サル
    Nao hontō wa Heisei sanjūnen jūgatsu dai rokujūyonkai jūyō-tōken ni shitei-sare
    This blade passed jūyō-tōken in the 64th jūyō-shinsa held in October of 2018.
  7. 于時令和元己亥年八月上浣探山識「花押」
    Koretoki Reiwa gan tsuchinoto-inoshishidoshi hachigatsu jōkan Tanzan shirusu + kaō
    Written by Tanzan (Tanobe Michihiro) in the first third of August of Reiwa one (2019), year of the boar + monogram
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