page_title: List of National Treasures of Japan (crafts: swords)
section_title: Ko-Bizen
hierarchical_section_title: List of National Treasures of Japan (crafts: swords) / Treasures / Old swords (kotō) / Bizen Province / Ko-Bizen
caption_attribution_description: Tachi signed "Made by Tomonari from Bizen Province" (太刀 銘備前国友成造, Tachi mei bizen no kuni tomonari tsuku). Heian period, 11th century, located at Tokyo National Museum
context_page_description: The term "National Treasure" has been used in Japan to denote cultural properties since 1897,
  although the definition and the criteria have changed since the introduction of the term. The swords and sword mountings in the list adhere to the current definition, and have been designated national treasures according to the Law for the Protection of Cultural Properties that came into effect on June 9, 1951. The items are selected by the Ministry of Education, Culture, Sports, Science and Technology based on their "especially high historical or artistic value". The list presents 110 swords and 12 sword mountings from ancient to feudal Japan, spanning from the late Kofun to the Muromachi period. The objects are
  housed in Buddhist temples, Shinto shrines, museums or held privately. The Tokyo National Museum houses the largest number of these national treasures, with 20 of the 122.
  During the Yayoi period from about 300 BC to 300 AD, iron tools and weapons such as knives, axes, swords or spears, were introduced to Japan from China via the Korean peninsula. Shortly after this event, Chinese, Korean, and eventually Japanese swordsmiths produced ironwork locally.
context_section_description: The oldest branch of swordmaking in Bizen Province is the Ko-Bizen (old Bizen) school. It was founded by Tomonari who lived around the early 12th century. The school flourished in the late Heian period (10th–12th century) and continued into the Kamakura period. Three great swordsmiths—Kanehira, Masatsune and Tomonari—are associated with the school. Ko-Bizen tachi are generally thin, have a strong koshi-zori and small kissaki. The grain is itame-hada or small itame-hada and the hamon is small midare made of nie in combination with chōji and gunome.
caption: Tachi signed "Made by Tomonari from Bizen Province"
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