Overview
This is a massive ōtachi (large sword) associated with Dazaengi Shrine, located on Ōmijima Island in Ehime Prefecture. It boasts an exceptional scale, reaching a blade length of 136.7 cm (approximately 4 feet 5 inches). The inscription clearly indicates that the sword was crafted by Chitein Nagayoshi during Sadaji 5th Year (1366 CE). Due to its overwhelming size, its magnificent appearance reflecting its era, and its excellent state of preservation, it is designated a National Treasure (kokuhō) among Japan’s finest swords.
Historical Background
The Northern and Southern Court period was an age when samurai frequently preferred using ōtachi (field swords)—which were significantly longer than standard weapons—to display their martial prowess. The inscription “Sadaji 5th Year” refers to the era name of the Northern Court, corresponding with the sexagenary cycle date “Bing-o,” placing its creation in 1366 CE.
The creator, Chitein Nagayoshi, belongs to the lineage of the Chitein school, a group of swordsmiths descended from the Yamato-den tradition. However, the elaborate and dynamic style of the blade’s temper line (hamon) suggests strong influence from contemporary trends, such as those found in the Sōshū school.
This sword was dedicated to Dazaengi Shrine, a renowned site revered by powerful warlords who considered it the “Guardian Deity of Japan.” It served as a hōnō-tō (donated sword), carrying strong symbolic weight as an offering and prayer from the samurai class during that tumultuous period.
Features and Appeal
The greatest appeal of this large sword lies in the fusion of its near-limitless size for practical combat use with highly advanced forging techniques required to support it.
- Overwhelming Scale: Measuring 136.7 cm in blade length and 4.8 cm in curvature, the sheer presence of the sword is commanding. To quench and finish such a massive piece without distortion requires extraordinary skill.
- Magnificent Form: It adopts the shape of a “great tip” (taishaki), featuring an extremely wide body (original width 4.8 cm) and a significantly extended point. This form conveys the powerful aesthetic unique to the Northern and Southern Court period.
- Intricate Forging and Tempering: The core steel (jigane) of the blade is exquisite, and the temper line (hamon) features a beautiful pattern combining small irregularities with interlocking waves. It possesses extremely high artistic completion, making it valuable as an art object.
- Historical Documentary Value: The inscription on the tang (nakago), “Sadaji 5th Year, Bing-o, Chitein Nagayoshi,” is invaluable epigraphy. It precisely identifies the year, sexagenary cycle date, and author, serving as a primary historical source essential for understanding sword manufacturing practices and dating standards of the Northern and Southern Court period.
Source: Excerpted from the National Designated Cultural Properties Database (https://kunishitei.bunka.go.jp/bsys/index)