The bokken (木剣, literally "wooden sword") or bokutō (木刀, the name generally used in Japan) is a Japanese wooden sword imitating the shape of the katana.
It can be used with the guard (tsuba) that protects the hands, or without the guard.
It is used in aikido, iaido, jōdō, kendo, kenjutsu and ninjutsu. It is also used as a weapon for chanbara training. Originally used for training, it has also become a weapon for combat.
The samurai Miyamoto Musashi is famous for his fights with the bokken, especially during his duel against Sasaki Kojirō. It is the weapon of choice for kenjutsu in most koryū.
Like katana, bokken have followed their time, and each historical traditional school - Tenshin Shoden Katori Shintō Ryu, Kashima Shinto Ryu, Yagyu Ryu, Yagyu Shinkage Ryu, Hyoho Niten Ichi Ryu, etc.
Each sword has physical characteristics, weight, curvature, length, point, thickness, adapted to the technique of this school. Today there are more than a hundred models, about half of which are still in use.
In Japan, the most commonly used term for a wooden sword is bokutō (木刀), with the term bokken (木剣) being a rarer synonym. However, it is the latter term that is most commonly used outside of Japan.
In Japanese, the character ken (剣) is preferably used at the beginning of a word for terms related to fencing, as in kendo (剣道, "way of the sword") or kenjutsu (剣術, "art of sword").
The character katana (刀, pronounced tō in multi-character combinations) is instead used as a suffix, as in shōtō (小刀, "short sword") and daitō (大刀, "great sword").
Most bokken are made in People's China, Taiwan and Japan. The former represent the majority of bokken sold as toys or souvenirs, while Taiwanese or Japanese bokken are more for martial arts practice.
There is also a production of bokken intended for the practice of martial arts in France.
Among the Japanese-made bokken, 90% come from the island of Kyūshū, especially from the city of Miyakonojō.
Many types of wood are used in bokken making: Japanese oak (white, denser, or red, lighter), buna (Fagus crenata), medlar (in Japanese biwa), yuzu (or isu no ki, of which the heartwood, sunuke, is used), and various types of ebony.
Oak provides a hard, tightly-fibered, impact-resistant wood. Loquat and sunuke provide a very fine grained wood and therefore soft surface bokken. Ebony bokken are much heavier and have an even finer grain.
The oak trees used to make Bokken are at least 70 or 80 years old, while other trees must be at least 200 years old to have large enough trunks.
In making a bokken, the trunk is first cut into longitudinal slices and then air-dried for a year. Some manufacturers use mechanical drying processes that shorten this time to a fortnight, at the cost of greater shrinkage of the wood fibers, producing bokken that are more sensitive to moisture and more brittle.
A pattern is then used to cut out the silhouette of the Bokken from the slice of wood, to cut the point and the edge
. Once the shape is roughened, the Bokken is cut by hand by successive planing with about twenty models of planers of different angles and curvatures. The finishing is done with fine sandpaper.
The differences between the manufacturers are first of all in the quality of the wood used, then in the type of the bokken hanger produced, which differ by the amplitude of their curvature and the position of the focus of the curvature.
As a training weapon, the type of quality expected of a bokken depends on the type of work sought.
In the case of single kata or cutting work, the aim is to get close to the feeling of the sword. The Bokken used must then have a balance and a hanger close to those of a katana.
For muscular reinforcement, there are bokken (suburito, "sabres for cutting") with a thickened blade, reproducing the weight (but not the balance) of a sabre.
When working with two armed partners (each with a bokken, or a jō in the case of jōdō and aikido, shock resistance becomes an important parameter.
The wood of the bokken must settle in the face of an impact, without producing splinters or sharp angles that could injure both protagonists. To achieve this, quality Bokken are cut along the length of the trunk so that the fibers run from one end of the Bokken to the other.
The blade part of the Bokken (called ha) is cut according to the purpose of the Bokken. In the case of the arts based on armed confrontation, the blade is smooth, ending in an acute angle, in order to reproduce the same type of contact as the steel blades of the swords.
In the case of aikido, where one of the partners may be bare-handed, the blade may be rounded and the point flattened to limit the risk of injury and to ensure better impact resistance.
Similarly, the position of the point of curvature, which determines the center of gravity of the weapon, is chosen according to a trade-off between maneuverability and power of the weapon.
Although less dangerous than a real sword, the bokken is nevertheless a weapon that can be deadly. For this reason, it is not used much in sports combat, especially in kendo where the shinai is used instead.
The bokken is used in most Japanese martial arts as a substitute for the katana. In some koryu, it is studied for its intrinsic qualities (as a weapon in its own right).
The koryu were born before the Meiji era. They are ancient schools that teach the art of samurai combat. They teach kobudō, ancient budō.
The koryu use the bokken for their practice of kenjutsu. They use it in katas with bokken against bokken, bokken against two bokken (one large and one small), bokken against naginata, bokken against kusarigama and even bokken against arrows.
According to Iwami Toshio Harukatsu, sōke of the Hyoho Niten Ichi Ryu, the exclusive choice of the bokken over the katana is based on Miyamoto Musashi's spiritual perspective of renouncing killing.
He also states that the use of bokken allows for the development of ki ("energy") from sword practice without physical damage.
In aikido and aikibudo, it is used both to materialize cutting directions used in empty hand techniques, as part of disarming techniques and as part of exercises where both practitioners are armed (this is then called aikiken) or in work close to jōdō, bokken against jō.
In iaidō, the bokken is used to work on the katas, to illustrate them, to warm up, to work on katas with several partners. It is the counterpart of the iaito. There are bokken with saya (scabbard) in order to get closer to the practice of the katana.
In judo, the bokken is used in the kime-no-kata.
In kendo, the bokken is used in kata.
In wadō-ryū, the bokken is used for tachi dori.
In shintō musō-ryū, the bokken is used by tori (the one performing the exercise) for these attacks against uke (the one undergoing the exercise) who counters with a jō.
There are variants of the bokken, either intended for specific types of technical work, or representing blades of different length than the katana. Among the most common are: