The learned promoter of the fine arts Johann Adam Duke of Questenberg (1678–1752) transformed his palace in the Moravian village of Jaromerice into a cultural center for Central Europe. In lively exchanges with renowned librettists, composers, and stage designers he realized nearly 200 performances of musical drama with the help of a superb interpretive ensemble of subjects and servants. The Duke was a musician, a music-lover and a Maecenas who modelled his music-dramatical productions above all on the Imperial Court in Vienna and the Italian centers of opera culture, and who built an international network of nobles and artists who helped him to form his musical collectioin. At the same time Questenberg was a Moravian patriot: he commissioned several operas to be performed in Jaromerice and played a central role in the music-loving aristocratic society of Moravia. Jana Perutková has compiled a comprehensive collection of rich archival sources (correspondence of all kinds, bills, inventories, lists of servants, registers, etc.) and expanded our knowledge of the Questenberg music collection based on research in libraries and archives throughout Europe in order to identify scores. Together with the libretti this makes possible a detailed description of musical activities in Questenberg’s Viennese palace and on his estates, especially in Jaromerice – from a musicological and dramatological as well as a general historical perspective. In addition, the nearly 500 surviving letters from Questenberg’s Viennese Hofmeister Georg Adam Hoffmann contain previously unknown information about musical and theatrical life at the Viennese Kärntnertortheater and at the Imperial Court, and about artistic personalities like Giovanni Bononcini, Nicola Porpora, Antonio Caldera or Giuseppe Galli Bibiena, and not least about the society of the Viennese court.