Among them is an album leaf by the writer, actor and lyricist Friedrich Wilhelm Gotter (1746-1797), who lived and worked in Gotha. A collection of twelve letters written by Eduard von Tempeltey (1832-1919), writer and Privy Cabinet Councillor of Duke Ernst of Saxe-Coburg-Gotha, to several addressees and on various occasions was also purchased. In addition, the library acquired a letter of congratulations for the New Year 1740 from Abbess Elisabeth Ernestine Antonie von Gandersheim (1681-1766) to Duke Luise Dorothea (1710-1767) of Saxe-Gotha-Altenburg.
Significant is the acquisition of a copy of the Erfurt Willkür of 1514, i.e. a collective manuscript documenting the development of city law in Erfurt and the writing down of customary law handed down orally in the context of the growing self-confidence of late medieval cities.
The estate of the Gotha cartographer Hellmuth Wolf was acquired for the Perthes Collection. Wolf concentrated on mapping extraterrestrial objects - the moon and Mars. His maps and globes of the Moon and Mars are important testimonies to 20th century Gotha cartography. Outstanding is Wolff's idea of a Mars globe, which was not realised, but whose comprehensive preliminary work is now permanently secured for research.
The Gotha Research Library also acquired a unique item of regional historical significance: the slim anthology contains three small prints on the history of Thuringia, which Johann Georg August Galetti (1750-1828), later director of the Gymnasium Illustre in Gotha, printed in 1774 with his two pupils Ernst Friedrich von Schlotheim (1764-1832) and his brother Carl von Schlotheim at Allmenhausen Castle. Ernst Friedrich von Schlotheim later achieved great importance in the history of science as a palaeobotanist and geologist. His estate is preserved in the research library.