Oskar Korschelt (1853 - 1940) was the author of the first extensive treatise on Go in a European language (German) entitled Das Japanisch-Chinesische Spiel 'Go' published in 1880. This article has been translated into English and published as The Theory & Practice of Go.
While working as an industrial chemist for the Japanese Government, Korschelt studied go in Japan with Honinbo Shuho and included in his own book much material from Shuho's book Hoen Shinpo. According to R. Schurig, Honinbo Shuho granted him 7 stones in 1880. His stay in Japan spanned 1876 - 1884.
Korschelt taught the game to Edward Lasker in 1907.