Koshu-ori adds refined beauty to Knot’s timepieces. Known for its delicate patterns woven from as many as 12,000 warp and weft threads, this textile has followed a unique path of development among Japan’s many yarn-dyed fabrics. Let us trace the history and origins of Koshu-ori.
Yarn-Dyed, Fine-Count, High-Density Silk Fabric
“Koshu-ori” refers to the woven textiles produced in the Gunnai region of Yamanashi Prefecture. Using pre-dyed fine threads woven at a high density, artisans create fabrics that are light in weight yet capable of expressing complex patterns and intricate designs. In recent years, Koshu-ori has gained popularity for umbrellas and neckties.
Its roots go back to the Edo period, when a luxurious silk fabric known as Kai-ki was developed. “Kai” is the old name for Yamanashi. The origin of silk weaving itself in Japan is said to date back to the Muromachi period, when thin Indian silk fabrics were brought on Nanban trade ships. By around 1630, silk weaving had spread nationwide, eventually reaching Kai. Though the land of Kai was not fertile for crops, mulberry trees thrived, fostering sericulture and the abundant production of high-quality silk threads. The region was also blessed with water ideal for silk weaving, and before long, textiles became an important tribute to the shogunate, establishing Kai as a major production area. As a result, Kai-ki became widely recognized as the premium silk textile of Gunnai.
The Hidden Elegance of Edo Merchants
With its shimmering beauty and feather-light weight, Kai-ki found a special place as a lining for haori jackets worn by merchants in Edo. Under sumptuary laws of the time that prohibited extravagant dress, merchants kept the outer fabric of their haori jackets subdued while secretly indulging in luxury, lining them with flamboyant Kai-ki. The popularity of Kai-ki is even referenced in Ihara Saikaku’s 17th-century literary works The Life of an Amorous Man and The Life of an Amorous Woman, which mention Gunnai stripes
In the Meiji period, as the government encouraged sericulture, the industry flourished further. However, after World War II, as the wearing of kimono declined, Kai-ki shifted toward uses in umbrellas and Western clothing. The raw materials also diversified beyond silk to durable fibers including cotton, hemp, polyester, and nylon. At the same time, production transitioned from hand looms to machine weaving, enabling even finer patterns and greater durability. Thus, the tradition evolved into what is now known as Koshu-ori (also called Gunnai-ori).
Today in the Gunnai region, in addition to machine production, each stage of the process – yarn twisting, pre-dyeing, pattern data creation, and weaving – is handled by specialized companies in a highly efficient system. This division of expertise allows Koshu-ori to maintain one of the highest levels of productivity among Japan’s yarn-dyed textile regions. Yet, it is not left to machines alone – the skill and experience of artisans remain essential to achieving the high quality for which Koshu-ori is known.
The process of stretching leather using a machine
It is the tireless dedication of these artisans, who continue to cherish Koshu-ori, that preserves its uncompromising Made in Japan quality.