Dmitri Mendeleev published his textbook Organic Chemistry in 1861.
The book appeared early in Mendeleev’s career, after he returned to Russia from scientific work in Heidelberg. It was written as a teaching text at a time when organic chemistry was expanding rapidly but remained difficult to organize for students. Mendeleev’s book presented the subject in a compact, systematic form and helped establish his reputation beyond his later work on the periodic law.
The publication also brought major recognition: the book won the Demidov Prize, awarded by the Petersburg Academy of Sciences. This was an important scientific honor in the Russian Empire and helped confirm Mendeleev as a leading young chemist.
Readers sometimes confuse 1861 with 1869–1871, the publication period of his much more famous Principles of Chemistry. That later work dealt broadly with chemistry and became closely associated with his periodic-system ideas; Organic Chemistry was an earlier, specialized textbook.