The world's oldest complete dated printed book is a Buddhist scripture from 868 AD

Found sealed in a cave in Dunhuang, China, the Diamond Sutra scroll carries a printed date corresponding to 11 May 868 — centuries before Gutenberg's press. It was made using carved wooden blocks, not movable type, but it remains the earliest printed book we can date with certainty.

— British Library, The Diamond Sutra — Or.8210/P.2, dated 868 AD