Uchi-katana vs. Tachi | How are They Different?

Hello everyone. Thank you for reading this article. I’m Shogo from Let’s ask Shogo, the interpreter of the online lessons and owner of this website.

Today, even in Japanese, when we say “katana,” we usually refer to the Uchi-katana. However, there are different katana types depending on their use, length, etc. Today, let’s learn the difference between the Uchi-katana and Tachi, the two types of katana that look the most the same.

The older type of katana is the Tachi, which has existed since the time the history of samurai started sometime during the Heian period (794~1185). It is basically intended to be used on horseback, with the blade down and hanging from the waist using an implement. It is generally longer and well-curved than Uchi-katana. The reason is that the Tachi is generally pulled out with one hand, so it is easier to pull it out if it is more curved. The length is also because it is more convenient for use on the battlefield.

On the other hand, Uchi-katana came into use mainly after the Sengoku period (1467~1615) ended. Since there were almost no wars during the following Edo period (1603~1868), people no longer had the opportunity to wear armor and there was no need to carry long Tachi. Uchi-katana, which are a bit shorter and not as curved, are carried in an obi (belt). The belt position of a Uchi-katana is higher than that of a Tachi hanging from the waist, so it is easier to pull it out with the blade facing upward. During the Edo period, a samurai was required to carry two katana, Uchi-katana and Wakizashi, at all times.

Thus, when explaining the difference between Tachi and Uchi-katana, the length, the depth of curvature, and whether the blade is turned up or down are often discussed. However, some Uchi-katana are long and some Tachi are short. Some Tachi have a shallow curvature, and some Uchi-katana have a deep curvature. The easiest way to tell the difference is to look at which side the inscription is engraved. The side on which the inscription is visible is called the “front side” of the katana. If the blade is down when viewed from the front, it is a Tachi, and if it is up, it is a Uchi-katana. For example, if the blade of a katana displayed in a museum faces down, it is a Tachi.

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