Tsuboya-yaki is one of Japanese traditional crafts. It is from Okinawa prefecture located in the south part of Japan. The features of Tsuboya-yaki are simplicity and powerfulness, and its traditional technique, firing temperature and clay peculiar to the area bring it a unique style, which makes us feel its weightiness and warmth. The feature of all Okinawa pottery, including preceding pottery of Tsuboya-yaki, such as Wakita-yaki and Kina-yaki, is influenced by China and Korea, and potters skillfully assimilated the skills of them and develop original style which suits the lifestyle in Okinawa prefecture.
Joyachi and Arayachi
Tsuboya-yaki is roughly divided into two categories; Joyachi and Arayachi. Joyachi is the main stream of Tsuboya-yaki, and it is fired at about 1200 degrees centigrade after glazing. The glaze itself is also peculiar to Tsuboya-yaki, and there are many kinds. Especially, Shirokasu is only in Okinawa since it is the mixture of calcium hydroxide and rice husk ash plus local clay of Okinawa prefecture (Gushikami white clay and Kise clay). The types mainly baked as Joyachi are plates, bowls and vases for daily use. On the other hand, Arayachi, also called as Nanban-yaki, is fired at around 1000 degrees centigrade without glazing. Main products are sake pots and water pots, and it is more dynamic and bigger compared to Joyachi.
The differences of the baking processes
These two categories are also differentiated by the baking processes. Joyachi is firstly dried completely and put into kilns. The kilns have some rooms inside, and potters move the pottery from one room to the other to give them perfect temperature. It usually takes 70 hours to bake completely. On the other hand, the kiln of Arayachi is tunnel-shaped. It takes around 55 hours to fire, but the length of baking highly depends on potters’ experiential knowledge since the condition of pottery is affected very much by the climate. The common point of these two types of kilns is that both of them are built on sloping ground.
Tsuboya-yaki was established about 300 years ago in Ryukyu Kingdom (which is now Okinawa prefecture). The Kingdom independently ruled its politic and commerce, and it prospered in overseas trades. Especially in 14th to 16th Centuries, a lot of pottery were brought to the Kingdom from China and other countries of the south. It is considered that the technique of Nanban-yaki is also brought at this time. In 1609, however, Satsuma domain (now Kagoshima prefecture) invaded Ryukyu Kingdom and put it under Satsuma domain rule. With the shift of its sovereignty, Ryukyu Kingdom’s prosperity of oversea trades declined, but the Kingdom did not give up to develop the technique of pottery. Ryukyu Kingdom invited Satsuma potters, who learnt earthenware in Korea, and put a lot of effort to acquire their skills. These attempts were successful in establishing Joyachi; the mainstream of Tsuboya-yaki. In other words, the invasion of Satsuma domain did not only give bad effect on the Kingdom. Furthermore, in 1682, three potteries – Misatoson chibana pottery (now Okinawa city), Shuri takaraguchi pottery, and Naha wakuta pottery – were integrated in the south of Makishi village and the village became present Tsuboya, Naha city. The king of Ryukyu Kingdom had been taking a positive attitude toward the development of Tsuboya-yaki, for example, he offered some parts of territories and some kilns to people as special places for religious purposes. Besides that, he exalted potters who rendered remarkable services to the same rank with the samurai class. Needless to say that these support by the king played important parts of the development of the pottery. However, even though Tsuboya-yaki had a strong backup, it did not spread well in Japan. The reasons are because of its geographical disadvantage (Ryukyu Kingdom consisted of islands; separated from other countries) and the lack of autonomy (it was governed by Satsuma domain.) It was the Meiji Restoration that Tsuboya-yaki got more opportunities to spread itself to all over Japan and other countries. The Meiji Restoration (Meiji Ishin) is one of the biggest turning points of Japan since the regime changed from the shogunate to the Emperor. This major turning point was a foothold for Ryukyu Kingdom to entry into a free competitive market.
In 1904, Russo-Japanese War broke out, and Japan had a boom. Many industries took the advantage of the boom. On the other hand, Tsuboya-yaki could not enjoy it since Arita-yaki, which is cheaper and lighter than other pottery, spread all over Japan and penetrated into people’s daily life. However the crisis did not last so long fortunately. In Taisho era (1912-1926), two Japanese potters; Shoji Hamada and Kanjiro Kawai; and a scholar of ethnology; Soetsu (Muneyoshi) Yanagi visited Okinawa and assisted potters to improve their technique and refine the style. Moreover, they brought Tsuboya-yaki to Tokyo, Kyoto, Osaka and Kobe, and introduced its outstanding traditional technique and its strength brought by the technique. Because of their enthusiastic effort, the quality of Tsuboya-yaki was recognized by many people. Not only Tsuboya-yaki was able to avoid becoming extinct, but also the potters retrieved their confidence and pride throughout this movement.
After that, in World War II, Okinawa suffered heavy damage from the ground war. Fortunately Tsuboya region was relatively less destroyed, so that it did not take a while until a reconstruction was finished after the war. As Okinawa was restored to peace and quiet, another difficulty arose for Tsuboya-yaki. It was an air pollution problem caused by firewood kilns. Since Okinawa is a small island and houses are clustered in some regions, the issue was very serious for people and also for potters. Naha city, the capital of Okinawa prefecture, decided to prohibit the use of firewood kilns in Tsuboya area. To cope with the policy, some potters started to use gas fired kilns or kerosene fired kilns instead (1970), and others who stick to firewood kilns moved to Yomitan village. Since Yomitan village is rich in high quality clay, potters who moved to this village established Yachimun village, a village of Japanese craft, in Yomitan village. In 1972, Okinawa finally returned to Japan. In 1985, Jiro Kinjo, a Ryukyu potter, is recognized as a one of Living National Treasures who preserve important intangible cultural assets in Japan. Nowadays, many tourists visit the village of crafts to look for their favorite pottery and learn about it. Tsuboya-yaki holds an established position as one of the best traditional crafts in Japan.