By Fred Weissberg 04/12

In 1338, two years after the brief Kemmu restoration, Ashikaga Takauji became the first Muromachi Shogun and established his government in Muromachi (Kyoto). Thus the Muromachi era began. Historically the early years of the Muromachi era from 1338 to 1392 are known as the Nanbokucho period.

The beginning of the Oei era (1394), however, is generally recognized in the sword world as the beginning of the Muromachi Era of sword production. The production of Bizen swords in Osafune during the Oei era was the greatly influenced by such smiths as Yasumitsu, Morimitsu, Ietsuke and others. These smiths left behind a large number of superb works.

The majority of their blades are constructed in lengths of around two shaku and four to five sun, although shorter works of two shaku and one or two sun are found. Hon-zukuri wakizashi of one shaku, two or three sun as well as hira-zukuri wakizashi of the same lengths are found in great number. During this time, they had a propensity to use a lot of horimono such as katana-hi with soe-bi, bonji, suken, and gomabashi in their hira-zukuri works. The tanto are without curvature and the majority are large-sized at about nine sun in length. While there are a large number of works done with a suguha hamon, there are also many works with a gunome-choji hamon.

Their kitae is mokume that is entwined with ji-nie and the hada is very well worked. Many have a jigane containing bo-utsuri, particularly the works of Yasumitsu and Morimitsu. However with Norimitsu and others a distinctive midare-utsuri can be found. Their boshi are ko-maru or pointed and have kaeri. There are also a large number of works found with a jizo style boshi. With the possible exception of tachi, it is characteristic of the nakago lengths to be considered so short as to be out of balance with the blade lengths. This fact led to the general speculation that the overall short sugata coupled with the short nakago meant that these swords made to be used with one hand.

With the onset of the Onin War in Kyoto (1467-1477) and the breakdown of the Ashikaga Shogunate system, the Sengoku period went into full swing . The Sengoku period, the period of the country at war, created a time of constant warfare between rival Daimyo lords thus greatly increasing the need for weapons. A side effect of this increased demand was that the quality and effort that went into producing the outstanding Bizen swords of the Oei era was in danger of becoming lost.

Because of the solid groundwork in sword production that was laid in the Oei Bizen period and before, Bizen smiths were able to produce large numbers of powerful swords for practical use. Also, since geographically Bizen Province, thanks to the Yoshii River, had a ready supply of top quality sand iron, it was relatively easy to obtain the iron necessary for manufacturing swords in quantity.

Sugata: Uchigatana were the main swords produced in this period, followed by the hira-zukuri wakizashi, tanto of either hira-zukuri or moroha-zukuri shape, and naginata. Uchigatana generally have a length of 63-66 cm, deep saki-zori, wide mihaba, thick kasane, full hiraniku, relatively small kissaki, and stout sugata. The nakago is short, to allow for single-handed use.

Just before the start of the Shinto era, swords became longer ranging from 72 to 75 cm. At this time the saki zori is relatively shallow. The nakago became longer for two-hand use.

Jihada: Fine ko-mokume hada with jinie is found and the utsuri is neither clear nor distinct.

Hamon:Usually we find a wide hamon of nioi deki but sometimes they were inclined toward nie deki. One of the most common hamon is koshi-no-hirata midare which is based on a wavy pattern and which is consistent in its width from bottom to top. Each top of the midare has a peculiar shape which is called kane-no-hasami (crab claw). O-midare, nie-kuzure, and hitatsura are also seen. Nioi-kuzure is seen on most Sue-Bizen swords. In the case of a moro ha-zukuri tanto that is midareba, the kaeri is in proportion to the hamon or becomes suguha and extends right down to the bottom.

Kissaki:Ko-maru sagari (descending) when the hamon is suguba. When the boshi is midare-ba, it is in proportion to the hamon, but the patterns on each side are different. The kaeri does not form a proper pattern, and it looks likehitatsura in the monouchi area extending down from the ko-shinogi about 6-9cm.

Nakago: Short and relatively less tapered nakago are found. Cho mei (long signature) is standard in the case of custom made works. Also included on the nakago are dates, second names (given names), and sometimes the owner’s name.


Unfortunately, as has been mentioned, the demand was so great that quality sword smiths using normal forging methods could not keep up with the increased demand. Further, the times were such that it became possible for swords produced by unskilled smiths to sell in great numbers. Such swords are called kazuuchi-mono (mass produced swords). These are swords that are generally carelessly produced and of inferior quality. Tens of thousands of such swords were exported to the Ming Dynasty of China during this period.

This does not mean that all Bizen swords produced during this period were kazuuchi-mono. Far from it, there were some truly great sword smiths who lived during the Muromachi era. The most recognizable name of this period is Sukesada. While more than eighty smiths using this name have been recognized, there are a handful of them who are acknowledged as making top quality swords. In particular Yosazaemonnojo's name is highly famed. In addition, Genbeinojo, Hikobeinojo, and Toshiro are the first names of prominent Sukesada smiths.

Other smiths of this period include Munemitsu, Katsumitsu, and Tadamitsu, all of who produced a large number of superb works. The Kiyomitsu name is also famed, particularly that of Gorozaemonnoj Kiyomitsu.

Generally most of the time, their blade construction was pretty close. The katana were about two shaku, one or two sun. From around the Tensho era and later, the lengths increased. The wakizashi are hon-zukuri as well as hira-zukuri, however the majority are hon-zukuri. As for tanto, many are what are called a yoroidoshi, i.e. small, without curvature, and very thick thus having the strength to pierce armor. Also a great number of moroha zukuri tanto can be found during this time. They also had a propensity to use a lot of horimono on their blades.

Their kitae is mokume mixed with itame that is somewhat course. However, there are works that have a very tight ko-itame hada< /em>. Many have bo-utsuri, however, the majority have an indistinct ji-utsuri. Many of the hamon are suguha, however, there is a mixing in of gunome-choji-midare which is called “kani-no-tsume” (crab claw). There are many works that have a very tight nioi-guchi. The boshi are ko-maru or o-maru as well as midare-komi. All are deeply tempered with kaeri that extend down the mune of the blade for a distance.

The nakago in comparison to the blade lengths is largely stubby and short. As the length of the blades tended to increase during and after the Tensho era, so did the length of the nakago. As for tanto, they are exactly the opposite of the longer swords, with the nakago being extremely long and unbalanced compared to the short length of the blades.

Among the blades of the Sue-koto period, there are a large number having inscriptions of the person ordering the blade. Additionally these carefully crafted blades are signed differently than are the mass produced blades. They are signed by the smith using the kanji, "Bizen no Kuni Jyu"; followed by his given name such as Yosazaemonnojo. On the other hand, the majority of the blades we find from this period are the poorer quality mass-produced kazuuchi-mono. These blades are signed "Bishu Osafune" followed by the smith's family name, i.e. Sukesada. Often they are signed with only the two-character signature Sukesada. This is an important way to distinguish the custom made blades from the mass produced blades.

This would be a good time to spend a few minutes on the characteristics of the kazuuchi-mono. As noted, they were mass-produced during this time of great need. Generally they were made by less skilled smiths who used less steel in an attempt to economize on tamahagane. This, of course, led to more flaws and the common appearance of shingane.

Here are the basic characteristics of the kazuuchi-mono:

Sugata: The nagasa is generally from 65 to 70 cm, and the sugata resembles Oei-Bizen but is a little more slender in the upper part.

Jihada:Shingane often appears on the surface as a result of the attempt to economize on valuable materials (tamahagane) and of the use of more shingane in the core. Rough masame-hada and tsukare utsuri (tired jihada or a jihada worn down from repeated polishing) also appear. When the shingane comes out into the hamon, the pattern of the hamon becomes obscured.

Hamon:There are many yaki-kuzure, and the pattern of the various midare is not at all regular. At a glance, the yaki-kuzure look likes the claws of a crab (kani-no-tsume).

Kissaki: Generally has yaki-kuzure and is different on each side of the blade.

Nakago:Kazuuchi-mono usually has the same style of signature, i.e. Bishu Osafune or Bizen no Kuni Osafune followed by the smith’s name, but without any zokumyo (given name).

In Tensho 18 (1590), there was a great flooding of the Yoshii River inundating the city of Osafune, destroying the access to the necessary raw materials, and killing most of the sword smiths. The trade of the sword smith had prospered in Bizen through centuries of both relative peace and warfare and, yet, in one brief period it was swept away by natural forces.

Within ten years of this event, the period of constant warfare ended when Tokugawa Ieyasu won the battle of Sekigahara and brought the stable peace of Tokugawa rule to Japan lasting more than 250 years. While the Bizen province continued to produce sword smiths and swords, it never again reached its former position of prominence.

The following sources were liberally plagiarized in the creation of this article:
The Connoisseur's Book of Japanese Swords by Nagayama Kokan
Nihon To Koza, Vol., Koto Part 3, translation by Harry Watson

The Outstanding Features of Bizen from Oei to Shin-Shinto, A lecture by Gordon Robson




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