Johann Hornung (c. 1660 – c. 1715) was a Baltic German clergyman, translator and developer of the Estonian language.
Hornung is likely to have been born in Tallinn. He worked as an inspector of schools in Estonia and as a pastor at Põltsamaa, Karula, Otepää, Hargla, Urvaste and elsewhere. During the Great Northern War, he was imprisoned by both the Swedes and the Russians; he also died in captivity in Russia.
Hornung was one of the language innovators who strove for a reform in orthography — simplification of the German-like spelling dating from the time of Heinrich Stahl (c. 1600–1657). In Grammatica Esthonica (1693), a grammar of the North Estonian language written in Latin as teamwork, Hornung presents the so-called old spelling system in a systematized and regulated form, which was significant for publishing both clerical and school literature. In Hornung’s presentation, written Estonian began to resemble more closely the spoken language. Together with Adrian Virginius, Hornung was the first to translate the New Testament into Northern Estonian; their translation became the basis for the 1715 edition. He published the spiritual handbook Önsa Luterusse Laste Öppetus (‘The Teaching of Blessed Luther for Children’, 1694) and was one of the compilers of Ma Kele Koddo ning Kirgo Ramat (‘Home and Church Book in the Language of the Land’, 1694–95).
A. K. (Translated by I. A.)