Johann Gottfried Pratsch (c. 1750 – 1818) saw his name Slavicized in various ways, as Jan Bohumír Práč in Czech and as Ivan (Иван Прач) in Russian. Of Bohemian extraction, he was born in Silesia in the mid-18th century and arrived in St Petersburg in the 1770s to work as a clavichord master and music teacher. Very little is known about his life in Russia, except that he was offered a position as a teacher in the recently founded school of the Academic theatre in St Petersburg in 1783.

Possibly, he was employed for a time in the household of Nikolaj Aleksandrovič L’vov (1753–1803), a renowned architect, academy member, amateur ethnographer, and collector of folk music. Inspired by Herder’s Volkslieder, L’vov, who was also an associate of a musical salon attracting famous poets like Deržavin and Kapnist, had collected folk songs during hunting expeditions and visits to relatives in rural Russia. In 1790, he invited Práč to write the musical notation for these songs. Sobranije narodnyh russkih  pesen s ih golosami (“A collection of Russian folk songs with their tunes”) contained an unsigned introduction on the genre by L’vov, although published under Prač’s name only. The song collection was not the first in Russia; Mihail Čulkov and Nikolaj Novikov had published four volumes under the title Sobranie raznyh pesen (“Collection of various songs“, 1770), and Vasilij Fedorovič Trutovskij had followed suit with a four-volume Sobranie russkih prostýh pesen s notami (“Collection of simple Russian songs with notes”, 1776-90). The Prač-L’vov collection, however, proved to be more influential in Russia’s musical development. It saw six re-editions, with more songs added. Some of the motifs set by Prač were taken up by 19th-century German composers, like Beethoven, Weber, and by Russian composers, like Musorgskij and Rimskij-Korsakov.