What Is a Katana?

Few things are as emblematic of Japan as the legendary katana. Its striking silhouette conceals the wealth of culture and heritage forged into every square centimetre of the sword.

The samurai's trusted sword, the katana has become one of the most magnificent works of art in the world, a symbol of social status and an enduring legacy of Japan's colourful past. But what is a katana?

Join us in this article to explore the mythical katana, its history and the way the sword symbolises the unshakeable spirit of the samurai.

What is a katana?

To create an accurate description of the katana, you need to know the origins of the word.

The Chronicles of Japan (Nihon Shoki), dating from the 8th century AD, are the first document to mention the term "katana". The second oldest classical history book of Japan describes the sword as having a single-sided blade ("kata" + "na"). This sets it apart from another Japanese sword, the "tsurugi", whose blade is double-sided or double-edged.

The iconic curve of the katana is more refined, or less pronounced, than that of the older, sabre-like "tachi". Its blade extends at least 23.86 inches or 60.6 centimetres from the guard ("tsuba") to the tip. The katana is also safer and steadier to handle, thanks to its exceptionally long handle, which can be held with both hands.

Drawing the katana from its "saya", or scabbard, is a flawless operation. The samurai were revered for their skill at cutting, able to strike in a single motion of the katana. This is possible because the cutting edge of the katana faces upwards.

And because the katana symbolises the samurai, it did not take long for the rest of the world to call this Japanese sword the "samurai sword".

A katana on display.

Attributes of a katana

The elegant, historic katana symbolises not only Japan and its legendary samurai culture. It is a work of art that no other culture can match or reproduce. However, a katana is not a katana unless it has the following characteristics.

• A moderately curved blade

One of the characteristics of the katana is its moderately curved blade. For those unfamiliar with the katana vs tachi debate, the blade of the latter has a more pronounced curvature. The katana blade has four essential features: the sori, the hamon, the jigane and the jihada.

• Sori (curvature of the blade)

Only a Japanese master swordsmith (katana-kaji) can define the curvature of the katana (known as the "sori"). Swordsmiths can position the shallow curve at the centre of the blade, near the guard of the sword, or closer to the tip of the blade.

Experts draw an imaginary line between the katana handle and the tip of the blade. They then measure the distance between this imaginary line and the back of the katana (the blunt side). The average curvature of a katana, or "sori", is about 1.5 centimetres.

• Hamon (the temper-line pattern)

Looking at a katana blade, you will notice that it shows two distinct shades. The product of centuries-old hardening, the "hamon" marks the division between the "soft" back of the blade and the "hard" cutting edge. This unique combination allows the katana to resist breaking and chipping while ensuring a razor-sharp edge for greater precision.

Although most people think the classic wavy "hamon" pattern is the best, there are other katana temper lines. They include clouds, arcs and more. However, the irregular, rough, wild look of "hitatsura" is beyond compare.

The temper lines of a katana, or "hamon".

• Jigane (surface of the blade)

Contrary to what Hollywood films portray, a katana blade is not reflective. It is also darker than other steels, thanks to the charcoal-like colours of the base material of the katana: satetsu, or tamahagane iron sand. This is why the two-tone katana has a dark grey spine and a light grey (almost whitish) cutting edge.

• Jihada (grain patterns)

These grain patterns are almost similar to the unique, ornate patterns of a Damascus blade. The "jihada" results from the complex, laborious process of heating, hammering and folding tamahagane steel, which creates swirls, waves and linear grain patterns. Sometimes the "jihada" shows a combination of different patterns.

• A standard-sized Japanese sword

Traditional Japanese swordsmiths (katana-kaji) still use the old system of measurement that their ancestors derived from the Chinese chi of ancient China: the "shaku". One "shaku" is approximately 10/33 of a metre, or 30.3 centimetres (about 11.93 inches).

The length of the katana must be at least 2 "shaku", or 60.6 centimetres or 23.86 inches, from the tip of the katana blade to the base of the katana (next to the guard of the sword and excluding the tang).

• The katana's tsuka (handle)

Most people refer to the "hilt" as the handle of the sword. Experts, however, do not use this term. The handle of the katana is the "tsuka", made up of the "tsuba" and other fittings.

• Tsuba (katana guard)

The guard of the katana does not only protect the hands from accidental cuts from the sharp blade. It also has a decorative function, allowing the katana to stand out as a work of art.

Although most katana guards are circular, some are rectangular but with rounded corners. The "mokko" is a unique style of tsuba because it has four distinct lobes. The sukashi tsuba has an ornamental cut-out, which makes it better suited to display than to use.

• Kashira and fuchi

Next to the guard of the katana sits the fuchi collar, while the pommel carries the kashira. These metal fittings can be as ornate as the tsuba without detracting from their fundamental function. You will also recognise the metal decorative piece, the menuki, beneath the wrapping of the katana handle.

A katana with an ornate dragon pattern on the tsuba. Photo: Sword Encyclopedia.

• Wooden saya (the scabbard)

The samurai sword is razor-sharp, so it is necessary to protect the wearer from accidental cuts. This is why craftsmen also create a special scabbard (the "saya") for the katana. The "shirasaya" is made of plain wood, while the "koshirae" is adorned with metal fittings on a lacquered scabbard.

The elements of a katana

People who see a katana for the first time cannot help but admire its beauty. Sword collectors around the world describe the katana as the most perfect, elegant and effective sword humanity has ever created. Three elements are essential for a katana to be a katana.

Artistic beauty

The katana blade alone is enough to win the admiration of anyone looking at a Japanese sword. Although Damascus blades also feature unique wavy patterns and other artistic designs, nothing can surpass the understated elegance of the katana blade. Where other blades cry out for attention, the katana does so in silence.

One can only salute the dedication and commitment of Japanese swordsmiths (katana-kaji). It is not easy to make authentic Japanese katanas, as the laws and regulations governing sword making are strict. It takes decades before an apprentice swordsmith can master the subtleties of making a katana.

Strength

Although modern metals are stronger than the iron used to make katanas, tamahagane remains a solid material for the revered Japanese sword. In the hands of an expert, the katana can make a clean cut in a single stroke. Of course, the results always depend on the person wielding the katana.

Precision

An expert swordsman can cut a lock of human hair with the razor-sharp edge of the katana. That says a great deal about the precision of this Japanese sword. However, the precision of the cut always depends on the person wielding the sword.

An elegant samurai sword on display. Photo: Just Fun Facts.

History of the katana

To know the Japanese samurai sword, you need to appreciate its history.

• Heian period

Between 782 and 1184, the traditional Japanese straight sword, the "chokuto", proved impractical as the samurai began to ride into engagements on horseback rather than on foot. One of the emperor's swordsmiths, "Amakuni", proposed redesigning the sword, giving birth to the tachi: a curved, single-edged sword. The tachi is the origin of the katana.

• Muromachi period

This era (1338-1573 AD), which the Japanese call "Sengoku", was marked by intense military conflict. With so many rival factions, swordsmiths improved the design of the tachi to make it quicker. The samurai of this period therefore used the "uchigatana", revered for its speed and precision. The katana-kaji forged two uchigatana swords, one short and one long. The shorter sword became the "wakizashi", while the longer version became the katana. It was not uncommon for samurai to carry both types of uchigatana.

Samurai warriors. Photo: Britannica.

• Momoyama period

Between 1574 and 1600, katana-kaji began adding ornaments to the uchigatana, such as precious metals and lacquer. Heavily decorated uchigatana became perfect gifts for the "hatamoto", or high-ranking samurai.

• Edo period

Between 1603 and 1867, the samurai began to wear the wakizashi, a short uchigatana, and the katana, a long-bladed katana, as a set. The uchigatana combination is called the "daisho". Samurai who wore the "daisho" at formal events and ceremonies had to follow rules.

• Meiji period

In 1876, wearing the katana and other Japanese swords in public became illegal, as the Meiji government sought to modernise its army. The Haitorei Edict marked the end of the katana as a sword of the battlefield, relegating its role to ceremonies and gifts.

The katana in the 21st century

Although the katana symbolises Japan, not everyone can own one. The Japanese government requires its citizens to buy a katana with verifiable historical or cultural significance. They can only buy a katana from licensed katana-kaji. Would-be katana owners must also register the samurai sword with the "Nihon Token Hozon Kai" in order to obtain a permit and a certificate of authenticity.

In Japan it is forbidden to carry a katana in public, even with a permit, as stipulated by the Firearms and Swords Possession Control Law. The samurai sword may only be displayed inside the home.

The bottom line

Although the katana is no longer carried into battle, its legendary status and unrivalled beauty continue to attract sword enthusiasts around the world. Its elegant, moderately curved look and the stunning design of its blade make this sword the most sought-after bladed object in human history.