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1656-00-00
Edo
About 18 min read
Nagasone Okisato, whose birth year is unknown and who died on the twenty-fourth day of the sixth month of Enpo 6 (1678), was a swordsmith of the Edo period. Having taken the tonsure, he adopted the priestly name Kotetsu, and is therefore also known as Nagasone Kotetsu Okisato or Nagasone Okisato Nyudo Kotetsu.
His origins are usually given as Nagasone village in Omi Province, but both an Omi theory and an Echizen theory exist and the question remains unsettled. Accounts of his birth year likewise diverge: some place it in Keicho 10 (1605) in Echizen, others in Keicho 1 (1596) at Nagasone in Omi. What is certain is that the Nagasone family was a group of general-purpose smiths who made their living as armorers.
The first half of Kotetsu's life was spent not as a swordsmith but as an armorer. This is not later conjecture but is attested by his own signature: he inscribed on his blades "shi hanhyaku kyoju Bushu no Edo" — "upon reaching fifty, residing in Edo in Musashi" — thereby recording himself that he moved to Edo and turned to sword-making at about the age of fifty. The Tokyo National Museum holds an "Oda kote" (a pair of armored sleeves) signed "Oite Bushu Edo kore o tsukuru" on the right sleeve and "Nagasone Okisato" on the left. Armor and helmets by his hand survive alongside his blades, evidence that his skill as an armorer came with him to Edo.
Behind an armorer's turn to sword-making lay a change in the times. Under the peace that followed the Osaka campaigns, large-scale battles ceased and demand for armor collapsed. One could not support a family by continuing to make battlefield harness. Edo, meanwhile, was growing rapidly as the seat of the shogunate, its warrior population swelling and generating new demand for blades.
Sources vary on the date of his move. Dealers and researchers have estimated it as before Meireki 1 (1655), while the statement that he went up to Edo and turned to sword-making in Meireki 2 (1656) is also widely repeated. The Tokyo Fuji Art Museum summarizes its holding as follows: "an armorer of Nagasone village in Omi Province, who by way of Echizen Fukui turned to sword-making around the beginning of the Meireki era at about the age of fifty, moved to Edo, and lived in Shitaya." All accounts agree on the essential point: the change came at the start of the Meireki era, at around fifty.
He did not settle in one place in Edo. He is said to have lived successively at Honjo Warigesui, Ueno Ike-no-hata, Yushima, and Kanda. In his later years he lived near the Ohanabatake in Ueno and inscribed his blades "ju Toeizan Shinobugaoka hen" (Toeizan being Kan'ei-ji, Shinobugaoka the hill of Ueno). The Important Cultural Property "katana, signed Ju Toeizan Shinobugaoka hen Nagasone Tora Nyudo, Kanbun 11, second month, a lucky day" (Shusui Museum of Art, Toyama Prefecture) is one blade bearing this residence signature.
As to his teacher, the accepted view holds that he studied under Izumi no Kami Kaneshige. His working period is reckoned at roughly twenty years, from the Meireki to the Enpo eras — an unusually short career for a swordsmith, within which he came to be regarded as the foremost master of the shinto period.
Kotetsu's blades can be dated approximately by the way he wrote his name. The characters used for "Kotetsu" changed over time: earliest was 古徹, then 虎徹 (known as "hane-tora," from the upswept final stroke of 虎), and finally 乕徹 ("hako-tora"). The 古徹 form belongs to the period before the Manji era (1658-1661), and 乕徹 came into use from about the autumn of Kanbun 4 (1664). Other diagnostic habits exist as well: the lower part of 興 sometimes reads as "i," giving the nickname "i-oki," and sometimes as 奥, giving "oku-ri."
The reason for such frequent changes is thought to be a countermeasure against forgery: his blades were famous for their cutting power and hugely popular during his own lifetime, and fakes proliferated accordingly. The evolution of the signature is itself evidence of his contemporary fame.
Kotetsu's blades show a shallow curvature, a compact kissaki, and a broad shinogi that lends the shape a sharp, taut character. The jigane is a finely packed, beautiful ko-itame; the hamon is notare with fine ko-nie densely gathered along the habuchi, bright and clear. Among his best-known effects is the "juzuba," a hamon of continuous rounded forms of uniform size like the beads of a rosary.
His cutting power was demonstrated by the formal tests of his day. Several of his blades survive with gold-inlaid cutting-test inscriptions by Yamano Kaemon Nagahisa, the official tester. Examples include the katana in the Tokyo National Museum signed "Nagasone Kotetsu Nyudo Okisato / (gold inlay) yotsu-do, cut by Yamano Kaemon at age sixty-eight, Nagahisa (kao), Kanbun 5, second month, twenty-fifth day," and the katana in the Tokyo Fuji Art Museum signed "Nagasone Okisato Nyudo Kotetsu / (gold inlay) Kanbun 5, twelfth month, sixteenth day, Yamano Kaemon at age sixty-eight, Nagahisa (kao), four bodies cut" — the latter measuring 70.1 cm in blade length with a curvature of 0.8 cm. Both record a "yotsu-do," four stacked bodies severed at a single stroke. The "Hachisuka Kotetsu," transmitted in the Hachisuka family of Tokushima domain, likewise bears a gold-inlaid inscription recording a two-body cut by Yamano Kaemon Nagahisa on the eleventh day of the eleventh month of Kanbun 5.
The most famous anecdote of his cutting power attaches to the "Ishidoro-kiri Kotetsu." This is a straight, curvature-less blade of two shaku one sun three bu (about 64.5 cm) bearing the added inscription "Nagasone Okisato Nyudo Kotetsu, Ishidoro-kiri." The name derives from the tradition that, demonstrating the blade's edge to the hatamoto who had commissioned it, he swung at a pine branch and carried through with such force that he cut into the stone lantern beside it. Honami Koson, in his Toudan Henpen, called it the most celebrated of all Kotetsu's works. Its unwarped configuration, evidently a special commission, is without parallel and stands out as extraordinary even among his blades.
In the Kaiho Kenjaku, published in Kansei 9 (1797), Kotetsu was placed in the highest rank, "saijo o-wazamono." He was rated, together with the Yamashiro master Horikawa Kunihiro, as one of the two "yokozuna" of the shinto period, and is regarded as the finest craftsman of the new-sword era. His adopted (or natural) son, the second-generation Nagasone Okimasa, was likewise ranked saijo o-wazamono, so the name did not end with one generation.
Popularity, however, bred forgery. False Kotetsu signatures were produced in quantity throughout the Edo period, and by the closing years of the shogunate figures such as Hosoda Naomitsu — known as "Kajihei" — were carving spurious signatures of many smiths. The sword scholar Sato Kanzan passed on a collectors' warning: "When you see a Kotetsu, assume it is a lie." Of the roughly two hundred blades registered as the work of Okisato, it is said that only twelve or thirteen are genuine.
This problem appears in its most famous form in the sword of Kondo Isami, commander of the Shinsengumi. In a letter dated the twenty-first day of the tenth month of Bunkyu 3 (1863), Kondo wrote that he possessed a daisho pair by Kotetsu, and in a letter written three days after the Ikedaya Incident he reported, "As for me, perhaps because my sword is a Kotetsu, I am unharmed." Yet accounts of how he obtained it differ wildly — that a dealer sold him a blade by Minamoto Kiyomaro as a Kotetsu; that it was granted by the Konoike house; that Saito Hajime bought an unsigned blade in Kyoto and passed it to him — and the prevailing view today is that Kondo's Kotetsu was not a genuine work of Okisato.
Several of Kotetsu's blades are designated Important Cultural Properties. The katana signed "Nagasone Okisato Nyudo Kotetsu," designated on 4 April 1928, is an exceptionally long blade of three shaku two sun five bu, made in Kanbun 2 on commission from Tokugawa Yorinobu, first lord of the Kishu branch; transmitted in the Kishu Tokugawa house, it was dedicated to Kishu Tosho-gu in 1927 and is deposited at the Wakayama Prefectural Museum. Others include a blade in private hands designated in 1949, blades designated in 1952 now at the Shusui Museum of Art and in the custody of the Japanese Sword Museum, and a blade at the Kyoto National Museum designated in 1959.
Among Important Art Objects is the tanto known as "Horaisan Kotetsu," bearing the three deity names Hachiman Daibosatsu, Amaterasu Kotai Jingu, and Kasuga Daimyojin together with a triple hollyhock crest, made around Kanbun 11-12 on commission from the Toda-Matsudaira house. Named blades include the "Urashima Kotetsu," a wakizashi dated the twelfth month of Manji 3 and transmitted in the Ikeda house of Tottori domain, carved with a figure identified as Urashima Taro, and the "Kaishu Kotetsu" (blade length 71.2 cm), so called because it was the favored sword of Katsu Kaishu. The Hikone Castle Museum holds a wakizashi that was the personal blade of the bakumatsu tairo Ii Naosuke, and the Edo-Tokyo Museum holds one of the few naginata by Okisato.
Kotetsu's move to Edo was not merely one craftsman changing trades. It was a double migration — from armor, a product whose demand had vanished, to swords; and from the provinces to Edo — and it illustrates how the arrival of peace restructured the industry of arms manufacture. If the experience of working iron as an armorer is understood to have issued in Kotetsu's characteristic construction, the tightly packed ko-itame and the tough, dense jigane, then his change of trade was not a rupture but the redeployment of accumulated skill.
Within a working life of only about twenty years he reached the summit of shinto sword-making, drew demand intense enough that forgeries circulated while he still lived, and left his name attached, by the end of the Edo period, to the legend of the Shinsengumi commander's blade. As the outcome of a change of career undertaken at fifty, it has few parallels in the history of the Japanese sword.