The Gottfried Wilhelm Leibniz Library (State Library of Lower Saxony, Hannover), as the former Königliche Bibliothek Niedersachsen, hosts a large collection of copperplates from the 17th and 18th centuries. The collection comprises about 850 original plates. In addition, there are a number of prints and drafts that obviously belong to the collection; related plates, however, are no longer extant.
Most of the plates were created for illustrations of historical genealogies, which were planned or edited within the framework of the Library.
The plates contain portraits of Lower-Saxonian monarchs over the centuries, illustrations of medals and coins, and also facsimiles of official documents on the history of Lower-Saxony and the Roman-German Empire.
About 100 plates are related to the "Ehrenkleinot des von Uhrankunfft Fürstlichen Hertzogen-Haußes Brunswig-Lüneburg" by Johann Heinrich Hoffmann, a work that was never published.
Leibniz considered reusing some of these plates for his publication on the history of the House of Welf.

Leibniz, after becoming head of the Königliche Bibliothek Niedersachsen, also saw to it that the famous engraver, Nicolaus Seeländer was employed in the Library.
Leibniz himself also had many ideas and proposals for illustrations, which he had drafted for the engravers. The Gottfried Wilhelm Leibniz Library (State Library of Lower Saxony, Hannover) presents within the ECHO collection digitizations of the copperplates as well as research data, which have been prepared with friendly permission by Reinhard Oberschelp, the author of Oberschelp, Reinhard: Kupferstichplatten in der Gottfried Wilhelm Leibniz Bibliothek. Katalog. Hameln: Niemeyer, 2005.