For many centuries Ainu women have spun threads from tree bark fiber, and woven fabric to make durable clothing for their families. Traditionally the Ainu had no written language and to establish the history of the fabric we must rely on Japanese written documents which state the demand for attoushi as a craft increased in the latter half of the 18th century as the trade between the Ainu and Japanese developed. According to one of the documents recorded by the Abashiri City History Editing Committee in 1958, in the year 1792 “Three rolls of attoushi and two rolls of attoushi with a hand length margin” were exchanged for “A bag of rice (approx. 14.4 liters)”. It seems that Ainu living in inland with no access to marine products, were developing crafts for trade. A boom of folk crafts had occurred in the 1930s and Nibutani-attoushi became a source of income for the Ainu people. Even men joined in the collection of tree bark and production of the fabric evolved into a proper local handcraft industry. Craft trading companies had increased the volume of purchases from the end of 1945. Labor was divided into the spinning of threads and weaving. The whole area focused their efforts into creating a mass production system for attoushi. Nibutani-attoushi, along with Nibutani Ita, became a traditional craft designated by the Ministry of Economy, Trade and Industry for the first time in Hokkaido in March 2013.

1. 1. Collecting tree bark Although there is no rainy season in Hokkaido, as trees hold more moisture than usual in June making them easier to peel, whole families would harvest bark from Manchurian Elms and Japanese Limes in early summer. Manchurian Elms with branches 15 – 20cm in diameter and with fewer joints are ideal for peeling. Using a hatchet, cuts are made 30 – 40cm above the base of the tree; only the surface of the bark is cut, as it is important not to damage the wood part. Peeling is delicate work requiring both hands to lift the bark straight up with the aim of removing a 7 to 8cm wide strip. The bark is worked free by twisting and shaking; the longer the strip the better, as this gives longer and higher quality threads.
   
2. 2. The coarse outer layer is peeled Mountains and the bark is taken home as soon as possible to prevent drying. The bark is bent and the coarse outer layer carefully and thoroughly peeled from the bent crack. Occasionally a hatchet is used to make it easier. The inside layer of the bark is folded and fastened by the same inside layer of bark.
3. 3. Softening the bark by boiling in water The collected inside layers of the bark are stretched and dried for 2 to 3 days; they can then be stored for many years. The dried inside layers of the bark are fastened in preparation for boiling with wood ash; this will soften the thinly layered inside layers and make it easier to separate them from each other. First the bark is added, the water brought to the boil again, ash added, and the pot covered with a lid and left to boil for several hours, making sure to thoroughly mix the contents to ensure even penetration of the alkaline brew into the bark.
   
4. 4. Peeling the bark while washing it in a mountain stream The bark is removed and any slime from the reddish brown bark is thoroughly washed out in a stream; slime weakens the threads. When the fiber layers come apart they are kneaded and peeled while being careful not to make the fiber too thin or uneven.
   
5. 5. Drying the fiber layers The fiber layers are hung outside on a pole or similar frame and left for about two weeks to dry in the sun. The sun takes out the reddish brown color and rain evens out the color.
   
6. 6. Shredding the fiber After drying, fibers are once again softened in water to make it easier to peel the inside layers as thin as possible so that each sheet becomes a single layer. Then each sheet of single layer fiber is shredded into 2mm wide strips and left to dry.
   
7. 7. Twisting threads and connect them with weaver’s knots to wind into skeins The shredded fiber is lightly twisted and spun using weaver’s knots to make one long thread; this is very time consuming and it is said that it takes almost a month to make one skein.
   
8. 8. Setting the warp threads to the loom As the warp threads should be longer than the length of fabric the work is mainly done outside on a windless day to prevent the thread becoming entangled and ensure even lengths. Two stakes are hammered into the ground some distance apart and the part of the loom, where the weft threads are set is attached to one of them. Threads are set by two people, one walks between the stakes feeding out the threads, and the other sets them on the loom. When this process is finished, the warp threads are fastened at 70 – 90cm intervals. The stakes are pulled up and the loom carried inside now ready for the weaver.
   
9. 9. Weaving while sitting Attoushi karape is an ancient loom that refers to the koshibata (backstrap loom). One end of the warp threads is fixed to a pillar or similar and the other end is fixed to the loom. Then, a weaver while sitting puts a cloth on their waist and pulls the threads through to weave. The woven fabric is rolled up and left on the floor while the weaver continues to weave while moving forward.