The study of anything often involves the sorting of elements into groups based on logical principles. Attempts are made to find common attributes, and beginning with very loose criteria and tightening them into more specific criteria, a body of information can become sorted out into a body of knowledge. It is this process of "sorting it out" that lets us establish a direction that allows us to achieve understanding of the subject matter at hand.

It applies to the study of Japanese swords, and the forms of classification that are in use are those we would expect from the study of art. We have determination of periods and changing styles, influences of peers and teachers, and regional associations, influences and differences.

Tradition, School, Lineage

These terms classify the work of a smith without much regard to the changes along the dimension of time. They are very useful as they allow us to know where a smith stands in relation to the influences of other smiths. There is some confusion, since in English we tend to interchange the use of school and lineage, and school and tradition. Similarly, there is some confusion on the Japanese side with the use of the word Den.


This is the broadest classification, in which the work of a smith is grouped with other schools formulating a general style. Their work can then be seen to be related in the large sense. The Japanese word that is used for this is Den. Example uses would be Goka Den (the Five Traditions) or Soshu Den (The Soshu Tradition). In English, we would interchange the Soshu Tradition with the Soshu School, which is probably something that we should not do to avoid confusion.

Knowing the tradition for a particular smith allows us to make predictions in very general terms about the output of his work. This is knowledge... based on one fact, we can predict another to some degree of accuracy. Similarly, if we are shown the work of a smith we have not considered in the past, through observation we can determine the tradition, and then through the tradition we can make predictions about geographical placement and regional influence.

The Goka Den concept itself (Yamato, Yamashiro, Bizen, Soshu and Mino Den) is an attempt to generalize the more specific traditions followed in the various regions of Japan (usually spoken of in the old provincial units). Because there are so many regions, it is necessary and useful to try to combine them into higher level constructs. This does imply that there is a regional component that fits between tradition and school, but this is indeed a more advanced subject requiring more study and in depth knowledge. Of course, this confirms the utility and necessity of the Goka Den concept.

In terms of this tradition classification, we are really speaking of Jokoto (generally swords with no curvature), Yamashiro, Yamato, Bizen, Soshu, Mino and the Shinto Den (new style swords) as our reason for study.

One very important thing to note is that if Den is used before the name of a swordsmith, it is not talking about a tradition. For example, Den Kinju or Den Niji Kunitoshi means in regards to an example of their work that it is not exactly the sum of their known characteristics.

In the case of these smiths where many unsigned works have been attributed, the characteristics are formed from old written reports and what can be observed in the realm of the signed works left to us. For smiths with only few (or no) signed works left, it makes it hard to establish a complete reference to their overall style. Given that a smith could work for decades, and styles evolved, it should be clear how difficult it can be to make a perfect reference out of a handful of examples. When Den is used like this, the work may be considered to have a small number of features that are over and above the expectations for the smith, or it may be missing a small number of features. It absolutely does not mean that the work was made (or possibly made) by one of the smith's students and it is not a mark of uncertainty of the attribution.


A good example of the use of School would be to consider the Bizen Tradition, and within this tradition we can identify the Osafune School, the various Ichimonji Schools, the Ko-Bizen School, and so forth. Each of the schools is tied together by the core elements of their tradition. The work of each of the schools though contains hallmarks that will make them unique from the others. In Japanese, I believe we are talking about the Ha. Similarly, we can consider the Hosho Ha, the Senjuin Ha, the Taema Ha, the Shikkake Ha, and the Tegai Ha in the Yamato Den as the example. Each school represents a large group of swordsmiths working together, and can be separated into various lineages.


The word used in Japanese for this would be Mon. The kanji character is the same word for gate, and there is an implication then of a family or a group of students or disciples. Various compounds using mon will bring about these various words in Japanese (fellow student, fellow disciple, family, etc.)

For a lineage, we are talking about a direct handing down of knowledge between a teacher, his students, and their students in an extended fashion. One can imagine then a school with several master smiths, and their individual students working side by side. You learn exactly what your teacher has to teach, and over time your own embellishments and style changes will come to your work. Your teacher works with other masters who are peers, working in similar styles because of their presence in the same school, but as they are individuals their work will usually evolve to be slightly different or their skills may be discernible. See Sadayuki

Fujishiro often writes things like "entered the Mon of Tsuda Sukehiro" or "entered the Mon of Bizen Motoshige." These are two examples of smiths who have a Tradition (Sukehiro = Shinto, Motoshige = Bizen), a School (Sukehiro = Osaka, Motoshige = Osafune) and now a lineage is being spoken of where a smith has come to take up a student/teacher relationship with the smith named.

Period and Era

Just as the above terms classify a smith based on his relationship to other workers in the same field, statements of period show the influence of historical realities in his work. In general, smiths working at similar times in history are facing similar realities (consider, state of technology, state of war or peace, etc.). So, it's clear they are often faced with a general and widespread influence on their work. By understanding the influence, and the results of that influence, we can make associations between style and period, and thereby have another means of classifying swords.

Key in this classification are written accounts (often simply information placed on the sword by the smith in terms of a signature and a date) that allow us to establish facts for when certain traditions, schools and lineages are active. Establishing period based on observable information closes the door on many possible determinations of the maker of a sword.

As above, there is some redundancy and interchangeable nature to the terms. What we hope to establish again is something along the lines of an orderly classification from general to specific. However, you will often see terms like "Koto period", "Kamakura period" and "Edo period." All of these are actually different ways of dividing up time, so there is no real unit or word we use in English to nail down just what exactly we are talking about. Technically, a period is a subdivision of era.


Era is essential to know. Just the combination of Tradition and Era allows us to know a lot about a smith and the kind of sword he would produce. Era is broken up into the following:

  1. Jokoto (pre 987 AD): technological advances had not yet allowed for the curved sword, and many competing styles of construction for various intended purposes were available to warriors

  2. Koto (987-1596 AD): the invention and acceptance of the tachi based on the curved sword design intended for cutting starts the beginning of this era, and the tanto has its heyday.

  3. Shinto (1597 - 1760 AD): this era picks up where koto leaves off. Katana replaces tachi, and the wakizashi is further developed. The unification of Japan caused a consolidation of some of the five traditions, and the failure of others. Regional differences unite based on loss of region-specific resources and the turn to a nation-wide marketplace for raw materials. Samurai class is formalized.

  4. Shinshinto (1760 - 1876 AD): a rejection of the conventional Shinto style and a return to fabrication of swords under the Goka Den marks this era, and it ends with the ban of wearing of swords, the elimination of the samurai class, and the collapse of an active market for sword manufacture.

  5. Gendaito (~1877 - 1945 AD): the beginning of this era is not clear, as sword manufacture continues as a trickle for special purposes, and begins to ramp up with the desire on the part of the Japanese armed forces to issue swords to officers during its increased military activity and attempts to expand its empire. Also features machine made swords for the first time in history, oil tempered swords, and generally low levels of quality. Such swords have no clear relationship with any previous traditions. Standout smiths and schools are in the minority, but do exist.


Statements of period are a bit more specific than those of Era, and are intended to zoom in on changes within the general time periods that caused specific changes to be adopted. Generally, period reflects the name of a ruler or reign... sometimes this is the name of an Emperor, or the name of a Shogun, or the name of the capital in which the Emperor or Shogun resided and from which he projected his power.

Examples would be things such as the Kanbun period, in the Shinto era where the rise of kendo and practice with wooden weapons caused a desire among warriors for, and the production of, fairly straight blades, or the Nambokucho period (the period of Northern and Southern Courts) with its long civil war and equally long horseborne tachi with massive kissaki and thin kasane.

If a period is quite long, it may be modified with a prefix of late, middle or early. In some cases we may even say "very late" if we know it is in the closing days of a period. Examples would be the Middle Kamakura, where swords became very wide throughout with little taper, and had a stout and short kissaki known as ikubi kissaki, or the Late Heian which was relatively peaceful and in which swordsmiths made beautiful, elegant and gentle blades.


In order to understand the sword as more than a simply beautiful piece of art, and to begin to master the art of kantei, a solid knowledge of the forms of classification is required. The characteristics found in the more detailed classifications such as region and period have to be known completely.

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