Johann Valentin Meder (1649–1719), born in Thuringia, spent most of his life on the Baltic Sea. He worked as a cantor, organist, kapellmeister and composer in Tallinn (Reval), Riga and Gdańsk. Meder's mobility meant that his work and influence became part of the musical history of several regions, cities and countries. Dieterich Buxtehude, among others, appreciated the ‘highly distinguished Mr Joh. Valentin Meder, who always finds pleasure in studying music of an unusual kind,’ and Johann Mattheson praised his modernity. The book examines Meder's work in relation to the local traditions of Tallinn, Gdańsk and Riga and illuminates his sacred vocal works in the context of music history. The study offers new insights into musical and cultural exchange in the Baltic Sea region.