What is Chokuto Sword

"Chokuto" refers to a sword with no curvature. This style of straight swords, prevalent during the era classified as "Jokoto" (old swords) from the Kofun period to the middle of the Heian period, was largely produced before the curved swords, known as "wanto" (curved swords), said to be the prototype of Japanese swords, were made. This article will introduce the basic knowledge of the chokuto and how it was used, and how it transformed into the wanto, along with some famous chokuto.

Nowadays Chokuto is more often seen as Ninjato, a straight katana used by Ninja.  If you want to buy a Chokuto, you can buy a custom ninjato which is almost the same. 

Introduction of Chokuto

"Chokuto" refers to non-curved swords used before the mid-Heian period. When the blade length exceeds 60 cm, it is expressed as "tachi" (large sword), and when shorter, it is expressed as "yokotachi". This is a different type from the curved, large swords known as "tachi", which were made later. Bronze and iron implements from the continent arrived in Japan during the Yayoi period. Those that arrived from the continent were bronze swords, double-edged iron swords, and single-edged ring-headed swords (sokantotachi: swords with a ring-shaped decoration on the pommel). There are various theories about when the forging of iron implements began in Japan, but the prevailing view is that it was around the late Kofun period.

Materials of Chokuto
Most of the swords produced at that time are archaeological finds, and because the blades are rusty and often not in their original form, it is impossible to determine a clear production date. On the other hand, the accompanying accessories (koshirae) are often found almost in their original condition, unlike the blade, so it is possible to guess what type of sword it was from the material and decoration. Straight swords produced from the late Kofun period to the Nara period contain not only iron but also a lot of copper, indicating that ironstone was used as raw material and that the folding and forging method, which is indispensable for Japanese sword making, had already been introduced. Also, over time, not only the pommel but also the fittings of the chokuto began to be decorated with gold and silver. It is said that luxurious chokuto were treasured by power holders as ceremonial swords used in ceremonies, offerings, and gifts, rather than for actual combat.

Chokuto and Warabiteto
Because the process of tempering a sword naturally causes it to curve, authorities such as the imperial court instructed their swordsmiths to ensure that the blades did not curve. However, as civilian swordsmiths became more active, there was less reason to insist on straight swords, and they began to increase the degree of curvature to improve sharpness, leading to the popularity of "wanto" (curved swords). Although straight swords fell out of favor as curved tachi became popular, they continued to be used by the Emishi people in regions such as the Tohoku region and Hokkaido until the late Kamakura to early Muromachi period. The Emishi preferred the "Warabiteto", which is a straight sword with a pommel decoration shaped like the bud of a fern (warabi).
As time went on, the blades began to curve gradually, transforming into the "kenukigata tachi", which became the prototype for the later production of Japanese swords.

Differences Between Straight Swords and Curved Swords
In addition to appearance, there are other differences between straight and curved swords. Straight swords are made in a "hirazukuri" or "kiribazukuri" style, which is easier and cheaper to produce than curved swords, making them suitable for mass production. They were also used more for striking and stabbing rather than slashing. On the other hand, curved swords are made in a "shinogizukuri" style. A "shinogi" is a part of the sword that runs vertically closer to the back (opposite side of the blade), which is one step higher. By making a sword in shinogizukuri style, the blade can be reinforced and made less prone to breaking. Also, with the introduction of the curve to the sword, it became possible to slash in a pulling motion.

Famous Chokuto

Ring-Headed Sword
A "ring-headed sword" (kantounotachi) is a straight sword with a ring-shaped decoration on the pommel.
At the Tosaninomiya Omura Shrine in Hidaka Village, Takaoka District, Kochi Prefecture, a "bronze ring-headed sword fittings" (kondosoukantoutachi) made at the end of the Kofun period has been worshiped as the sacred object for over 1,000 years. Most of the swords from the same period were excavated through archaeological surveys, so this sword, which has been kept indoors, can be said to be a valuable historical material. It is a ceremonial sword intended for use in ceremonies, not practical use, and is characterized by stylized openwork carving on the pommel. It is open to the public during the "Autumn Festival" held every November 15th.

uiryuken
The "Suiryuken" is a straight sword that was made during the Nara period. It is said to have been the sword carried by Emperor Shomu, and was housed in the Shosoin in Nara City, Nara Prefecture. In 1872 (Meiji 5), it was passed on to Emperor Meiji, and the goldsmith for the Imperial Household, Natsuo Kano, was ordered to make the sword fittings, which were completed a year later in 1873 (Meiji 6). Emperor Meiji named the sword "Suiryuken" and wore it.
Shichiseiken
The "Shichiseiken" is a straight sword that was made during the Asuka period. It is said to have been owned by Prince Shotoku (Prince Umayado), and its name derives from the fact that the Big Dipper is inlaid in gold on the blade.
It's not a sword meant for actual combat, but was made for the purpose of protecting the nation and warding off evil spirits. At Shitennoji in Osaka City, Osaka Prefecture, there is a national treasure, a Shichiseiken made of iron, and at Horyuji in Ikoma District, Nara Prefecture, a Shichiseiken made of bronze still exists.
Futsunomitama
"Futsunomitama" is a straight sword said to have been made from the late Nara period to the early Heian period and appears in the Kiki Mythology (the collective name for the Kojiki and Nihon Shoki). It has many other names such as "Futsunomitama Sword", "Saji Futsu God", "Mika Futsu God", "Kotomuke Sword/Kunimuke Sword", etc. It's a divine sword that is said to be able to rule the country with a single swing, and it is said that Emperor Jinmu used this sword to establish Japan.
After Emperor Jinmu's ascension to the throne, Futsunomitama was buried in the mountain of Isonokami in Yamato Province (now Nara Prefecture). This is the origin of the Isonokami Shrine in Tenri City, Nara Prefecture, and it is said that Futsunomitama still rests in the inner sanctum of the worship hall with the divine treasures.
At Kashima Shrine in Kashima City, Ibaraki Prefecture, there is a straight sword, a national treasure over 270 cm in length, which is called the second generation Futsunomitama (according to the shrine tradition, it is referred to as Futsunomitama Sword). The official name of the sword is "Straight Sword Black Lacquer Hyomon Tachi Koshirae". You can still see it at the Treasure House of Kashima Shrine.