Kabuto

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

Japanese helmets dating from the fifth century (long before the rise of the samurai class) have been found in excavated tombs. Called mabizashi-tsuke kabuto (visor-attached helmet), the style of these ancient helmets came from China and Korea and they had a pronounced central ridge.

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 o 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"). Also, kabuto o nugu (lit. "to take off the kabuto") means to surrender.

The basic parts of the kabuto include:

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.

A small opening in the top of the kabuto, called the tehen or hachimanza (seat of the war god, Hachiman), was thought 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. The tehen was usually decorated with tehen kanamono, which were rings of intricately worked, soft metal bands often resembling a chrysanthemum.Zunari kabuto and momonari kabuto were two helmet forms that did not usually have an opening at the top.

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