Japanese blue-and-white pottery is known as Sometsuke, literally “dye applied”, because the colour was likened to traditional indigo-dyed linen. The ceramics are decorated by hand, stencil or transfer-print with a blue pigment, traditionally cobalt oxide, over which a transparent glaze is then applied, and once fired the underglaze decorations become a vivid shade of blue. This method originated during China’s Song dynasty (960-1279) and is believed to have been perfected around the beginning of the Ming dynasty (1368-1644). Blue-and-white pottery was introduced to Japan at the start of the 17th century in the form of export Tianqi or Ko-Sometsuke ("Old Sometsuke") porcelain from Jingdezhen, which was imitated in the kilns at Arita before spreading to other areas including Kyoto, Seto, Hasami and Mikawachi, each developing their own unique variations of Sometsuke.
Besides Ko-Sometsuke, the kilns at Jingdezhen were simultaneously producing Shonzui (also Shonsui) wares for export to Japan. These dazzling blue-and-white wares with their meticulously handpainted blocks of patterns were of a considerably higher quality than the deliberately coarse and simple Ko-Sometsuke style, which appealed to the wabi-sabi tastes of Japanese tea masters at the time.