Several decades after Gutenberg's death, Gutenberg's claim to inventing the printing press was contested.

Johannes Schöffer - a grandchild of Gutenberg's journeyman Peter Schöffer - maintained that his grandfather had invented the printing press. This led to a reevaluation of Gutenberg's role. Thereafter the birth of printing was attributed to various persons and places in historical studies.

J. D. Köhler, Ehren-Rettung Johann Guttenbergs (Vindication of Johann Gutenberg) 1741

Thus, for two hundred years, there was uncertainty about who had really invented printing. It was Johann David Köhler, a professor for history in Göttingen who, in 1741, using both the Helmasperger Instrument and other historical source documents as evidence, vindicated Gutenberg.

This marked not only the beginning of modern research on Gutenberg but also reinstated Gutenberg as the sole inventor of the printing press.

Chapter
The Impact of Printing