We’re back for another look at how the arms and armor of samurai developed, and this time we learn why they ditched their otachi for uchigatana.

Last week, we took a trip through samurai history, examining how the armor worn by Japan’s warriors changed through different eras of Japan’s past. Of course, it wasn’t just the defensive nature of warfare that shifted over time, and Japan’s samurai swords also evolved.

Once again, our guide on this journey is the Fukuoka City Museum’s ongoing Samurai: The Beauty and Pedigree of Warriors exhibit. With nearly 150 pieces on display, there’s a lot to look at, but let’s start in the late years of the Heian period (which lasted from 794 to 1185).

▼ A blade from swordsmith Tomonari of Bizen (present-day Okayama Prefecture), with a protracted curve that starts almost immediately after the hilt.

Despite all the dramatic martial arts movie narration you may have heard about the sword being the soul of the samurai, it wasn’t always their most useful weapon. For several centuries, archery was what set a samurai apart on the battlefield, as conflicts were often fought by well-funded warriors firing arrows at each other from horseback. Eventually, though, commanders started looking for ways for foot soldiers to take down mounted foes, which led to long, slender-curved swords meant to be used to cut the legs of a rider’s horse out from under him. This continued into the early years of the Kamakura period (1185-1333), during which polearms such as the naginata and nagamaki also rose in prominence.

But as you might remember from our discussion of samurai armor evolution, samurai lords began building more and more castles in the years following the Kamakura era. With cavalry ineffective for either side in a siege, foot soldiers became increasingly important, and hand-to-hand fighting became a more prevalent part of military conflicts. Armor became lighter and more form-fitting, since it no longer needed the large gaps between plates that horseback archers required to ride and shoot. In response, swords became larger and heavier, characterized by the weapons called otachi in the Nanbokucho period (1336-1392).

With their curve shifted to the mid-point of the blade, otachi were designed to hack and slash with, since you had to cut through armor and were trying to outright kill your opponent, not simply hurt his horse’s bare shin and render it unable to run.

However, fighting on foot also meant that samurai had to conserve their stamina, and running around swinging bulky otachi for an entire battle wasn’t always the best strategy. So in the Muromachi and Sengoku periods (1336-1600), preferences changed again, with samurai now favoring the shorter, straighter uchigatana. These katana were particularly suited to close combat, with a balance between swiftness and cutting ability. They were also easier to quickly draw from a sheath, enabling them to remain popular even as Japan’s age of armored combat came to a close.

Some otachi which had been forged in earlier times were even modified by their Sengoku period owners. For example, the Heshikiri Hasebe was forged roughly 200 years before it was wielded by warlord Oda Nobunaga, who had its tang (the metal protrusion that extends into the sword’s handle) shortened, brining its size closer to that of an uchigatana.

Another unique aspect of the Heshikiri Hasebe is that the entire blade was quenched when it was forged, resulting in dramatic tempering lines across its entire face.

Speaking of tempering marks, the Nikko Ichimonji. A certified Japanese national treasure from the Kamakura period, the Nikko Ichimonji’s has a series of flower petal-shaped temper colorings near its tip.

Also part of the exhibit and another national treasure, at just 54 centimeters (21.3 inches) long the Raikunitoshi is the shortest sword in Japan to bear that distinction.

But if you’re of the mind that bigger is always better, the museum is also showing the longest national treasure sword, the 159-centimeter Bishu Osafune Tomomitsu, an intimidating blade forged sometime around 1360, when otachi influences were still being felt.

The exhibit also includes a number of tanto (daggers), with the Taiko Samonji, once again a national treasure, with a crystal-like sparkle historians call jinie.

We also had a chance to look at another piece from master smith Samonji Genkei, who worked during the mid-1300s, in the form of his Yoshimoto Samonji.

However, while the tang bears Samonji’s mark, the blade itself has temper lines quite unlike the jagged patterns regularly associated with his work, leading some to speculate that the sword was retempered by another smith at some point in time.

While the Yoshimoto Samoji was only on display until October 6, there’s still plenty to see in the exhibit, which runs until November 4.

Museum information
Fukuoka City Museum / 福岡市博物館
Address: Fukuoka-ken, Fukuoka-shi, Sawara-ku, Momochihama 3-1-1
Open 9:30 a.m.-5:30 p.m.
Closed Mondays
Admission 1,500 yen (US$14)
Museum website
Exhibition website

Photos ©SoraNews24
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