The Perthes Collection, acquired by the Free State of Thuringia with the support of the German Federal Cultural Foundation in 2003, forms the core of the modern holdings of the Gotha Research Library. It comprises the holdings of the Justus Perthes Geographic Publishing Houses in Gotha and Darmstadt as well as those of the Hermann Haack Geographic Cartographic Publishing House in Gotha, a publicly owned company. The Justus Perthes Publishing House was founded in 1785 in the connection with the Gotha court. Perthes took over the publishing of the Gotha Court Kalendar/Almanach de Gotha, which became the most important lexicon of the European aristocracy in the 19th century.

The scientifically interested Duke Ernst II of Saxe-Gotha-Altenburg collected atlases and geographic literature and invited Franz Xaver von Zach, one of the most famous astronomers of his time, to Gotha. Zach built Germany’s first freestanding astronomical observatory on the Seeberg hill in Gotha and trained the Gotha court lawyer Adolf Stieler in cartography. In 1810, Stieler presented Justus Perthes with the idea of an atlas, which made the Perthes Publishing House one of the leading cartographic and geographic publishing houses of the 19th and 20th centuries. Beginning in 1855, the publishing house became internationally renowned through its journal Petermanns Geographische Mitteilungen.

The Perthes Collection documents the last phase of the Age of Discovery, in which the interior of the non-European continents and the polar regions were explored. At the same time, it provides unique insights into the map production of the 19th and 20th centuries.