Grube is principally remembered for his pioneering studies of three little-known languages, two spoken in the
Amur region of the
Russian Far East, and one extinct language spoken by the
Jurchen people of
Manchuria. At the behest of the
Saint Petersburg Academy of Sciences, Grube worked on the linguistic materials brought back from the Amur region by
Carl Maximowicz and
Leopold von Schrenck during the 1850s. Based on these materials, in 1892 Grube published a vocabulary of the
Gilyak language (a
language isolate, also known as Nivkh), and in 1900 he published a vocabulary of the
Gold language (a Tungusic language, also known as Nanai). By the nineteenth century, the Jurchen language that had been spoken by the ancestors of the
Manchu people during the
Jin dynasty (1115–1234) was almost completely unknown, and the few surviving inscriptions in the
Jurchen script were undecipherable. However, in the early 1890s the
Royal Library at Berlin acquired a manuscript copy of the
Vocabulary of the Bureau of Translators () from
Friedrich Hirth which included a chapter on the Jurchen language that was missing from other known copies of this book. and it has remained the principal source for the study of the Jurchen language ever since. In addition to his linguistic studies, Grube also published extensively on Chinese philosophy, religion and mythology. He was also interested in Chinese literature, and posthumously published a German translation of the Chinese mythological novel,
Fengshen Yanyi ('The Investiture of the Gods'), as well as German translations of a set of Chinese
shadow play scripts. ==Works==