Nagasone Okisato (1599 - 1678) was a famous armorer from Echizen noted for the indestructibility of his helmets. A lay priest, Nagasone signed his work with the name Kotetsu, (old iron) because this is what he used for his work. At age 54 he moved to Edo and began making swords.

Kotetsu Katana
74.5cm

One possibility for this change is that the peaceful later half of 17th century made for less of a demand for armor. But there is a well-known story that explains this sudden change another way: It was proposed one day by the Daimyo of Echizen that one of Kotetsu’s helmets be tested by a sword made by Kiyomitsu, a famous smith from Kaga province. The helmet was placed on a specially constructed wooden stand and Kiyomitsu himself drew the sword and gathering his concentration raised the sword above his head. Kotetsu noticed the extreme focus of Kiyomitsu’s intent and, sensing that the helmet might be penetrated, called out for him to stop. He calmly walked over and adjusted the helmet, and told the sword maker to continue. Kiyomitsu, who was visibly flustered by this, took his position again but had lost the intensity of focus, and when he struck, the blade only did superficial damage to the helmet. Kotetsu’s reputation as an armorer remained intact, the ploy had indeed worked, but Kotetsu felt so guilt-stricken that after apologizing profusely to Kiyomitsu he quit the trade and left the province.

Kotetsu Katana
Iwakuni Art Museum

In his new career as a sword smith Kotetsu took his inspiration and style from Go Yoshihiro, one of Masamune’s ten brilliant students. At one time he was noted for the elaborate engravings he put on his blades. It is thought that these carvings were done to hide flaws in the forging process of his early work. Later, as his work matured, he simplified by changing his focus to developing a supreme cutting ability. Because of this, the only ornament to his later blades is a Juzuba-style hamon that has the look of Buddhist prayer beads. These blades are lined with bright and tightly packed nioi and nie that make for a very strong edge. This is a result of his mixing in old iron from nails, pots, kettles and scrap iron with newer tamahaganae, a technique derived from his unique knowledge gained as an armorer and not employed by his contemporaries. His work was in great demand; however, Kotetsu also had the reputation of being an eccentric who rarely filled the orders for his swords. To meet the demand for his work, many forgeries were made and signed with his name. In fact, there are so many false Kotetsu blades that experts say, ‘if you had 100 swords signed Kotetsu, they might all be forgeries’.

Kotetsu Katana

One story of Kotetsu relates how he was commissioned by a samurai to make a sword. When the blade was done the warrior came to pick it up. Noting that it was quite plain-looking the Samurai complained that the price, 100 pieces of gold, was too expensive. Kotetsu, feeling a bit insulted picked up the katana, walked over and cut the top off a stone lantern. There was not a scratch on the blade. The Samurai, duly impressed, said, “I’ll take it. Here are your hundred gold pieces.” The sword smith then told him, “It’s no longer for sale.”