The fifty-volume Digest on Statecraft (Ch. Qhunshu Zhiyao; J. Gunshochô) was compiled in China in 631 by Wei Jen, an official in charge of the Imperial Library, on the orders of Emperor Taizong (r. 627-650) of the Tang dynasty (618-c. 907). A crucial work for understanding Chinese political thought of the period, it was also read by Japanese officials under Emperor Ninmyô (r. 833-850) in the early Heian period (794-1185) and was considered an extremely important book by later Japanese emperors.
The Tokyo National Museum owns thirteen volumes, which were passed down in the aristocratic Kujô clan. These were copied in the mid-Heian period from a manuscript prepared in China in the Tang dynasty and are the oldest surviving copies of the text. Each of the handscrolls was made by joining sheets of paper dyed in shades of colors such as purple, pale blue, and brown, as well as sheets decorated with "flying-clouds" (J. tobikumo). The paper was then ruled with gold guidelines, and the text copied in a decorous Japanese style. Several people worked together to copy the text, inserting annotations about variant texts and grammatical aids for reading the Chinese.
These volumes are unusual in that Chinese works were seldom copied on colorful paper such as that used here. Because of the beauty of both the paper and the brushwork, parts of this manuscript were also cut into segments and treasured in later generations as fragments of early exemplary calligraphy (J. kohitsugire).