Munetsugu’s given name was Koyama Sobei and he was born in 1802 in Shirakawa province in Oshu Prefecture. He was also known as Issensai or Seiryôsai. He was the younger brother of Koyama Munehira and Koyama Munetoshi. He was a member of the Katô Tsunahide Mon and he also studied sword making under Tsunahide’s younger brother Chounsai Tsunatoshi. Later Munetsugu went to Edo and worked as a retained swordsmith of Lord Matsudaira of the Kuwana family.
In the second year of Koka (1845) he received the title of Bizen no Suke. It is believed that he was given this title because of his expertise in producing swords in the Bizen tradition. True to the Bizen tradition, most of his blades display a chôji-gunomemidarehamondone in nioi deki. There are also some works that are made in suguhato emulate the Ko-Aoe style of workmanship. He produced many fine blades from around 1830 up until the beginning of Meiji.
Having worked in both Owari province and Kuwana, he frequently traveled back and forth eventually settling down in the Yotsuya Samon-cho area of Edo. It appears that Munetsugu collaborated with the Yamada family of professional sword testers, especially Yamada Yoshitoshi and Yamada Asauemon Yoshimasa, the head of the family. As the clan smith of the Kuwana clan, the Han samurai often subjected his blades to cutting tests. For that reason, there are many of his blades surviving with cutting tests.
Many of these tests seem to have taken place at Senju where there was a famous execution ground or Denma-cho prison. Most of these tests seem to have taken place in the Tenpo era when Munetsugu was at his peak in his thirties. The blade presented here for sale has one such cutting test stating that it took place at the prison grounds.
Munetsugu died in 1872 at the age of 70 and is rated at least as highly as the other important smiths of the Shinshinto era such as Masahide, Naotane, Unjusai Korekazu, and Chounsai Tsunatoshi, especially in the area of Bizen den works.
The blade presented here is signed by the smith on the omote Koyama Munetsugu Saku (made by Koyama Munetsugu). It is also dated on the omote as follows, Tenpô Kyunen Hachi-gatsu Hi (made on a day in August of the ninth year of Tenpô (1838). Thus, Munetsugu would have been 36 years old when he made this blade. Blades made by Munetsugu during the Tenpô era (1830-1845) are considered to be his some of his best work.
The reverse (ura) of the blade contains the cutting test. It reads, Dônen Jû-gatsu Tokka Oite Rôyashiki ((Same year (1838) on October 10th at Royashiki prison). Taitai Dotanbarai Kirite Yamada Goro (shoulder cut on an earthen mound cut by Yamada Goro). It is unusual to find a cutting test that states it was a “TaiTai” (cut through the shoulders). This cut is rated as the second most difficult cut following the “Ryo kuruma” (cut through the hip bones).
This is a very wide and powerful blade with the sugata for which he is famous. The nagasa is 70 cm or 27.56 inches. The width at the moto-haba is 3.2 cm or 1.26 inches and the width at the saki-haba is 2.1 cm or .083 inches. The kasane is 0.84 cm or 0.33 inches. The sori is koshi-zori of the Bizen style measuring 1.61 cm or 0.63 inches.
The jitetsu is excellent being an o-itame hadawith some mokume. His jitetsu is bright and clear. While he is most famous for his large regular chôji in the Bizen Ichimonji style, he occasionally made hamon in other styles. This blade is an excellent example of that. While there are definitely areas of chôji here and there, the overall hamon is done more in a style of a peaked gunome-midare that in parts reminds us of the teeth of a saw. It is nioi deki, of course, and there are many activities such as ashi, kinsuji, etc. throughout the hamon. The bôshi is stretched and the temper is notare with a short kaeri (turn-back). The blade is in wonderful polish with only a couple of very small surface scratches that are barely noticeable.
This blade comes with a nice set of koshirae that could be original to the blade. The tsuba is iron and of the Higo school. The balance of the metal fittings are of shakudo, gold, silver, and copper and depict shishi frolicking. This katana was awarded Tokubetsu Hozon papers by the NBTHK in 2010 attesting to the validity of the signature, the cutting test, and the quality of the blade.