The oldest surviving book printed with movable metal type is Korean, not German

Printed in 1377 at a Korean Buddhist temple, 'Jikji' used movable metal type 78 years before Gutenberg's press appeared in Europe. Its one surviving volume was taken to France in the early 1900s and now sits in the Bibliothèque nationale de France, recognised by UNESCO as a Memory of the World.

— Compiled by the monk Baegun, Jikji — printed at Heungdeoksa temple, 1377