Dō-maru kabuto. Muromachi period, 15th century, Tokyo National Museum, Important Cultural Property

Kabuto of gusoku (Tosei-gusoku) armor European-style cuirass, 16th - 17th century, Azuchi-Momoyama - Edo period, Tokyo National Museum

Kabuto (兜, 冑) is a type of helmet first used by ancient Japanese warriors which, in later periods, became an important part of the traditional Japanese armour worn by the samurai class and their retainers in feudal Japan.

Note that in the Japanese language, the word kabuto is an appellative, not a type description, and can refer to any combat helmet.

History

Japanese helmets dating from the fifth century have been found in excavated tombs. Called mabizashi-tsuke kabuto (visor-attached helmet), the style of these kabuto came from China and Korea and they had a pronounced central ridge.^[1][2]

Kabuto, which is now known as a samurai helmet, first appeared in the 10th century Heian period with the appearance of ō-yoroi. Until the early Muromachi period, kabuto were made by combining dozens of thin iron plates. Generally, only daimyo and samurai at the rank of commander wore kabuto ornaments called tatemono (立物), which were shaped like a pair of hoes. In the middle of the Muromachi period, as the number of large-scale group battles increased, ordinary samurai wore tatemono in the shape of hoe, sun, moon or flag on their kabuto to show their courage or to distinguish friend from foe.^[3][4]

In the Sengoku period in the 16th century, when the war became extremely large-scale and the guns called tanegashima became popular, the armor styles called ō-yoroi and dō-maru became outdated and the armor style called tosei-gusoku (当世具足) was born. tosei-gusoku kabuto are made by combining three to four pieces of iron plates, and they are more bulletproof than the conventional style, enabling mass production, and the tatemono became more eccentric and huge. Some of these tatemono were made of iron, but for safety reasons on the battlefield, they were sometimes made by putting paper on a wooden mold, coating it with lacquer and curing it, and extracting the mold. In the Azuchi–Momoyama period, tosei-gusoku kabuto had a simple yet more unique and bold design in accordance with the popularity of Momoyama culture.^[3][4][5]

In the Edo period, when the Tokugawa shogunate defeated the Toyotomi clan at Summer Siege of Osaka and the society became peaceful, armor with a revival of the medieval times became popular, and ō-yoroi and dō-maru style kabuto were made again.^[5]

The kabuto was an important part of the equipment of the samurai, and played a symbolic role as well, which may explain the Japanese expressions, sayings and codes related to them. One example is Katte kabuto no o wo shimeyo (lit. "Tighten the string of the kabuto after winning the war"). This means don't lower your efforts after succeeding (compare to "not to rest on one's laurels").^[6] Also, kabuto wo nugu (lit. "to take off the kabuto") means to surrender.^[7]

Parts of the kabuto

1. hachi
2. shikoro
3. fukigaeshi
4. mae-zashi
5. hari-date
6. datemono
7. hachimanza

The basic parts of the kabuto include:

• Hachi, a dome composed of overlapping elongated plates called tate hagi-no-ita
• Tehen, a small opening at the top of the hachi, usually fitted with a tehen kanamono (an ornamental grommet, often resembling a chrysanthemum)
• Mabizashi, a brim or visor on the front of the hachi
• Ukebari, a cloth lining inside the hachi
• Tsunamoto, mounting points for attaching crests
• Kasa jirushi no kan, a ring at the back of the hachi for securing a kasa jirushi (helmet flag)
• Fukigaeshi, wing-like or ear-like projections to the sides of the hachi
• Shikoro, a suspended neck guard composed of multiple overlapping lames
• Shinobi-no-o (chin cord), often used to secure the mengu (facial armour)

A typical kabuto features a central dome constructed of anywhere from three to over a hundred metal plates riveted together. These were usually arranged vertically, radiating from a small opening in the top. The rivets securing these metal plates to each other could be raised (a form known as hoshi-bachi) or hammered flat (a form known as suji-bachi); another form, called hari bachi, had the rivets filed flush. Some of the finer hachi were signed by their makers, usually from one of several known families, such as the Myochin, Saotome, Haruta, Unkai, or Nagasone families.^{[citation needed]}

A suji bachi kabuto with the cords tied under the chin; note the prominent front crest, the recurving fukigaeshi, and the shikoro composed of hundreds of interlaced scales

A small opening in the top of the kabuto, called the tehen or hachimanza (seat of the war god, Hachiman), was thought^{[according to whom?]} to be for passing the warrior's top knot through. Although this practice was largely abandoned after the Muromachi period, this opening may have been retained for purposes of ventilation or simply as an artifact of how the plates were riveted together.^[8] The tehen was usually decorated with tehen kanamono, which were rings of intricately worked, soft metal bands often resembling a chrysanthemum.^[8][9] Zunari kabuto and momonari kabuto were two helmet forms that did not usually have an opening at the top.

Kabuto incorporated a suspended neck guard called a shikoro, usually composed of three to seven semicircular, lacquered metal or oxhide lames, attached and articulated by silk or leather lacing, although some shikoro were composed of 100 or more small metal scales in a row.^[10] This lamellar armour style, along with kusari (mail armour), was the standard technology of Japanese body armour, and some shikoro were made of mail sewn to a cloth lining (a form called kusari shikoro).

The kabuto was secured to the head by a chin cord called shinobi-no-o, which would usually be tied to posts or hooks on the mengu (facial armour) or simply tied under the chin.

Kabuto are often adorned with crests called datemono or tatemono;^[11] the four types of decorations were the maedate (frontal decoration), wakidate (side decorations), kashiradate (top decoration), and ushirodate (rear decoration). These can be family crests (mon), or flat or sculptural objects representing animals, mythical entities, prayers or other symbols. Horns are particularly common, and many kabuto incorporate kuwagata, stylized antlers.

Types of kabuto

A suji bachi kabuto

Suji bachi kabuto

Suji bachi kabuto is a multiple-plate type of Japanese helmet with raised ridges or ribs showing where the helmet plates come together; the rivets may be filed flat or they may be left showing, as in the hoshi-bachi kabuto.

Hoshi-bachi kabuto

Hoshi-bachi kabuto (star helmet bowl) with protruding rivet heads, have large rivets (o-boshi), small rivets (ko-boshi) and a rivet with a chrysantemoid-shaped washer at its base (za-boshi). Hoshi-bachi kabuto could also be suji bachi kabuto if there were raised ribs or ridges showing where the helmet plates came together.

Hari bachi kabuto

Hari bachi kabuto is multiple-plate Japanese hachi with no ribs or ridges showing where the helmet plates come and the rivets are filed flush.

Zunari kabuto

Edo period iron zunari kabuto

The zunari kabuto is a simple, five-plate design.

Tatami kabuto

A great number of simpler, lightweight, folding, portable armours for lower-ranking samurai and foot soldiers (ashigaru) were also produced. These were called tatami armour, and some featured collapsible tatami kabuto (also called choshin-kabuto), made from articulated lames.^[9][12][13] Tatami kabuto did not use rivets in their construction; instead, lacing or chain mail was used to connect the pieces to each other.

Kaji kabuto

Kaji kabuto were a type of helmet worn by samurai firemen.^[14]

Jingasa

Jingasa were war hats made in a variety of shapes, worn by ashigaru (foot soldiers) and samurai, which could be made from leather or metal.^[15]

Kawari kabuto, or strange helmet

During the Momoyama period of intense civil warfare, kabuto were made to a simpler design of three or four plates, lacking many of the ornamental features of earlier helmets. To offset the plain, utilitarian form of the new helmet, and to provide visibility and presence on the battlefield, armorers began to build fantastic shapes on top of the simple helmets in harikake (papier-mâché mixed with lacquer over a wooden armature), though some were constructed entirely of iron. These shapes mimicked forms from Japanese culture and mythology, including fish, cow horns, the head of the god of longevity, bolts of silk, head scarves, Ichi-no-Tani canyon, and axe heads, among many others. Some forms were realistically rendered, while others took on a very futuristic, modernist feel.