
The earliest written history of Japan, which was a mixture of reality and mythology, mentions only four terms relating to color, mainly representing the categories of dark, light, bright, and vague. Over time, these ancient terms evolved to mean 白 shiro (white), 黒 kuro (black), 赤 aka (red), and 青 ao (blue/green) .
This initial lack of chromatic variety, in a people who today certainly pay particular attention to the visual aspects of reality, should not come as a surprise: various studies highlight how color is a cultural fact rather than a perceptual one and show how the clear distinction between green and blue appears later in language. This is in contrast to the distinction between white, black, and red. So much so that some languages had, and sometimes still have, a single term that combines the two tones of blue and green into one word.
Even some of the most important classical texts of our civilization are no exception. They are very precise in some descriptions, but not in those relating to color gradations. For example, in the Iliad and the Odyssey, Homer uses the term glaukòs, which indicates green, blue, and gray. Sometimes even yellow or brown. For this reason, it is used interchangeably to define the color of water, eyes, leaves, or honey.
But let's return to the distinction between blue and green in Japan.
Towards the end of the millennium, in the Heian period from 794 to 1185, midori 緑, the Japanese word for green, made its first timid appearance. But even then, it was still considered a shade of blue! This inevitably created a certain ambivalence. Even today, there are green things named with terms belonging to the blue category: aoringo 青林檎 (blue apple), which is actually green. Green bamboo is called aodake 青竹 (blue bamboo).
This brings us to the history of the traffic light in Japan called 青信号 Aoshingoo. The first traffic light was imported from the United States in 1930 and clearly had a green light. Despite this, official documentation referred to the traffic light with the word ao (blue) rather than midori (green). The insistence of linguists that the appropriate term midori be used and the need to comply with international customs regarding traffic lights led to a compromise. In 1973, the government imposed, by cabinet order, that traffic lights use the bluest shade of green possible, still technically green, but noticeably blue enough to legitimately continue using the nomenclature ao. While modern Japanese allows for a clear delineation between blue and green, the concept of blue still encompassing shades of green remains firmly rooted in Japanese culture and language.

JAPANESE BLUE
It is still a plant that connects us ideally with Japan. Previously, it was Silphium, an extinct plant whose seed led to the current form of the love emoji. (Find the incredible story at the following link: A HEART-SHAPED EMOJI )

This time, it is a plant that is still cultivated in Japan. We are talking about Persicaria tinctoria, a flowering plant of the Polygonaceae family imported to Japan from southern China: indigo. The blue color of the samurai, Japanese blue! 藍い (ai). It is also considered the color of love because of its assonance with 愛 (ai) love.
Indigo is the oldest vegetable dye known to man, used for thousands of years in places such as ancient Egypt, where mummified remains wrapped in indigo-dyed fabrics have been discovered. It entered Japan via the Silk Road around the 8th or 9th century and, as with so many other things, soon took on its own unique Japanese touch.
The use of indigo dye went through three phases in Japan. The first, during the Heian period (794-1185), saw it used as the color of the highest nobility.

The woodblock print by ukiyo-e master Hiroshige, Wakamurasaki, shows Prince Genji glimpsing Lady Murasaki for the first time. Court life in the Heian period (794-1185), where the story takes place, was characterized by brightly colored kimonos, but Genji's kimono in Wakamurasaki stands out because it is a softer dark blue with a white square pattern. This is one of the first glimpses of indigo dyeing in Japan.

The second period was in the 12th century, when samurai wore indigo garments under their armor as they were useful for protecting their skin from various ailments and cooling it down. It also had antibacterial properties, as sword wounds infested with bacteria healed more quickly.
A lesser-known reason for the samurai's love of indigo is that its liquid color is called “kachi” in Japanese. This is also the word for “to win,” making indigo indispensable to the superstitious Japanese warriors of the time.

The third and final phase of evolution took place during the Edo period (1600-1868). It was then that indigo became widely used, so to speak. The Shogun had forbidden ordinary people from wearing overly bright colors, limiting the choice of colors for clothing to muted shades such as blue, brown, or gray. This allowed indigo, with its aesthetic and functional properties, to spread rapidly. Cotton and hemp also proved relatively easy to dye with indigo, as only nobles were allowed to wear silk at that time.
Soon, indigo became all the rage in Japan, as everyone from merchants to farmers—who, like the aforementioned samurai, found many practical uses for its medicinal (and insect repellent) properties—began to use indigo in virtually every aspect of their daily lives. It is no wonder that R.W. Atkinson, a British chemist, when he visited Japan in 1874, saw so many indigo-dyed fabrics, even among the common people, that he labeled the color “Japan Blue.”
Indigo is also fireproof and can withstand temperatures of up to 815°C. It proved indispensable in protecting the fledgling fire department during the terrible fire of March 2, 1657, west of Edo (now Tokyo).

The Edo period was largely peaceful, and this gradually changed the role of the samurai in society. The Confucian samurai elite were supposed to stay away from “petty commercial concerns,” but the evolving economy also meant an evolving samurai class. They could no longer ignore their daimyo's (feudal lords) interest in trade. Indigo production thus also became a valuable export product.
PRUSSIAN BLUE
The most famous ukiyo-e print of all, Hokusai's The Great Wave off Kanagawa (1830-1831), makes extensive use of blue.

The pigment used is Prussian blue, a synthetic color imported into Japan from the Netherlands starting in 1820. From then on, a veritable “blue revolution” spread, with the proliferation of woodblock prints entirely in blue called aizuri-e.
SYMBOLISM OF THE COLOR BLUE
Purity
Blue symbolizes everything that is pure and transparent, like the sky. As in most cultures, purity is a highly valued quality in Japanese culture. Newborn babies are usually wrapped in blue fabrics. Blue is also often worn by pregnant women and women seeking husbands. Blue has a similar connotation in many cultures, probably because of its association with water sources. It may also be because blue is one of the pigments naturally obtained, especially in Asian countries, from indigo plants. Before the era of synthetic pigments and industrial dyes, indigo was a popular and widely used coloring agent in clothing. For this reason, various auspicious occasions and gatherings involved people wearing blue clothing.

Interestingly, weavers and people in charge of dyeing fabrics were known to wear white and not blue.
Femininity
Blue is a popular choice for clothing in Japan and the favorite color of over 40% of the population according to a 2019 survey. It is the most widely used color in kimonos, worn by women. The color blue is associated with virginity and femininity. This is interesting when compared to the Western perception, where blue is the color of men and pink is the color of women. Western choices for girls and young women rarely involve blue items. The concept of an ideal woman in ancient times had a lot to do with purity of mind and body. The association of blue with femininity is probably also due to its association with purity and innocence.

IN SPORT
Football
Blue is also the color of the Japanese national football team's jersey. The players are called the Blue Samurai, and it seems that this color was retained because, wearing it, the University of Tokyo team, which represented the country at the Far East Championship in 1930, won the first game of the championship. So, over time, the blue jersey has been kept, in true Japanese superstitious style. Blue is generally considered one of the lucky colors.

The Olympic logo

Blue was chosen for the Tokyo 2020 Olympics, and needless to say, the shade chosen was indigo.
English 日本語 中文 한국어 BahasaIndonesia Français Português Русский Español Deutsch Italiano