From 1820 down to the later 19th century, the Vietnamese State ordered some 152 books to be published at state expense. These included volumes on the history and geography of Vietnam, biographies of Emperors and some of their senior officials, military affairs, legislation, social and political affairs, religion, culture, and verse and prose. Also included were editions of the Confucian classics and academic studies in Confucianism, designed to be used by the scholars giving lectures in the Van Mieu-Quoc Tu Giam (the Imperial College in the Temple of Confucius). These books were written in Chinese and Chinese transcribed Vietnamese.
Printing Chinese was traditionally done by using woodblocks, into which a whole double-page spread would be carefully cut. Illustrations were cut the same way. Since these books were published by imperial order, the woodblocks were prepared with the greatest care. The wood used was of the highest quality, and the calligraphy and workmanship were equally good. Many, indeed, are themselves works of art. Once printed, the woodblocks were carefully preserved so that second and successive editions could easily be printed as needed. The whole process, from seeking an initiating imperial decree, writing and editing the texts which were mostly based on official documents, through cutting and checking the woodblocks, printing, and finally the safe-keeping of the preserved woodblocks, was the responsibility of a special state agency, the Office of Historiographers. Today 34,555 of these woodblocks remain. They have always been regarded as a state treasure and the collection was inscribed on the International Memory of the World Register in 2009. They are not only central to the 19th century history of Vietnam but are also an important reminder of the role of the state in promoting education through publishing material of this sort.