Step 1: Recall the history of early printing. Printing originated in China using woodblock techniques long before Gutenberg's printing press in Europe.
Step 2: Identify the earliest dated example. The oldest known complete, dated, and printed book is a copy of the Diamond Sutra, a Buddhist scripture.
Step 3: Provide context. This copy was found in a sealed cave in Dunhuang, China, in the early 20th century. It is a scroll, about 16 feet long, printed from woodblocks, and includes a colophon stating that it was made in "the 9th year of Xiantong of the Tang Dynasty," which corresponds to the date May 11, 868 CE. The Biblia Pauperum is a block-book from the 15th century in Europe.